THE PROJECT FOR FORMULATING MASTER PLAN ON ...The Project for Formulating Master Plan on Development of Geothermal Energy in Ethiopia Executive Summary Final Report Table 1.1 Target

JR

IL

15-055

The Federal Democratic Republic of Ethiopia

Geological Survey of Ethiopia (GSE)

THE PROJECTFOR FORMULATING MASTER PLAN

ON DEVELOPMENT OF GEOTHERMALENERGY IN ETHIOPIA

FINAL REPORT

APRIL 2015

JAPAN INTERNATIONAL COOPERATION AGENCY (JICA)

NIPPON KOEI CO., LTD.JMC GEOTHERMAL ENGINEERING CO., LTD.

SUMIKO RESOURCES ENGINEERING ANDDEVELOPMENT CO., LTD.

JR

IL

15-055

The Federal Democratic Republic of Ethiopia

Geological Survey of Ethiopia (GSE)

THE PROJECTFOR FORMULATING MASTER PLAN

ON DEVELOPMENT OF GEOTHERMALENERGY IN ETHIOPIA

FINAL REPORT

APRIL 2015

JAPAN INTERNATIONAL COOPERATION AGENCY (JICA)

NIPPON KOEI CO., LTD.JMC GEOTHERMAL ENGINEERING CO., LTD.

SUMIKO RESOURCES ENGINEERING ANDDEVELOPMENT CO., LTD.

Ethiopia

Location Map

Great Rift Valley

1

2

3

4 5 6

7 8

9

10

11 12

13 14

16

17

18

19

20 15

21 22

Source: Google Earth Pro

The Project for Formulating Master Plan on Development of Geothermal Energy in Ethiopia

Executive Summary Final Report

THE PROJECT FOR FORMULATING MASTER PLAN N DEVELOPMENT OF GEOTHERMAL ENERGY IN ETHIOPIA

EXECUTIVE SUMMARY

1. BACKGROUND AND PURPOSE OF THE PROJECT

1.1 Background The total installed capacity of electricity power plants in Ethiopia amounted to 2,100 MWe, as of

January 2010; more than 90% are of hydropower. Under such circumstances, the Ethiopia electric

sector addresses the development of indigenous energy such as geothermal and/or wind power, with

recognition of the importance of energy diversity and energy mixture.

Among other indigenous types of energy, geothermal energy has become more important as a base

load power. Geothermal potential survey was commenced in Ethiopia in 1969. Since then,

step-by-step potential surveys have identified more than 16 promising geothermal sites for electricity

development. However, development stages vary from site to site, only two sites, i.e., Aluto Landano

site and Corbetti site, are being developed towards commercial operation.

The Geological Survey of Ethiopia (GSE) requested the Government of Japan for technical

assistance in formulating a master plan for geothermal development including technical capacity

building for geothermal development. In response to the request, the Japan International Cooperation

Agency (hereinafter referred to as “JICA”) dispatched the JICA Project Team to Ethiopia for the

implementation of “The Project for Formulating Master Plan on Development of Geothermal Energy

in Ethiopia” (hereunder referred to as “the Project”).

1.2 Objectives and Scope of Work of the Project

1.2.1 Objectives The objectives of the Project are as follows:

1) To conduct geothermal surface survey;

2) To prioritize geothermal prospects with a unique set of criteria;

3) To formulate the master plan for geothermal development based on the above; and

4) To contribute to capacity development of GSE under the process of formulating the master

plan.

1.2.2 Counterpart and Relevant Organizations The counterpart organization and the Joint Coordination Committee are as follows:

1) Counterpart:

Geological Survey of Ethiopia (GSE), Ministry of Mines of Ethiopia

Nippon Koei Co., Ltd. JMC Geothermal Engineering Co., Ltd Sumiko Resources Exploration & Development Co., Ltd.

S-1

April 2015



2) Joint Coordination Committee (JCC)

i) Ethiopian Organizations

Director General of GSE / Chief Geologist of GSE

Director of Geothermal Resource Directorate, GSE

Representative from the Ministry of Mines (MoM)

Representative from the Ministry of Water, Irrigation and Energy (MoWIE)

Representative from the Ethiopian Electric Power (EEP)

Representative from the Ministry of Finance and Economic Development (MoFED)

ii) Japanese Organizations

Resident Representative of JICA Ethiopia Office

JICA Project Team

Other personnel concerned to be proposed by JICA

iii) Observer

Representative from the Embassy of Japan

Note that EEPCo was restructured in December 2013 into two companies: a) Ethiopia Electric

Power (EEP) responsible for power generation and transmission, and b) Ethiopian Electric Utility

(EEU) for delivering electricity services (distribution, and sale of electric power). The EEP will be

managed by the Ethiopian CEO, whereas the EEU will be managed for two years by an Indian

company (Power Grid Corporation).

1.2.3 Target Sites The target sites are listed in Table 1.1 below. The approximate locations are shown in the location

map at the beginning of this report.


S-2

April 2015



Table 1.1 Target Sites

Geothermal Sites Prioritization /

Data base Remote Sensing

Site Survey

1 Dallol ☑ ☑ GSE 2 Tendaho-3 (Tendaho-Allalobeda) ☑ ☑ ☑ 3 Boina ☑ ☑ GSE 4 Damali ☑ ☑ GSE 5 Teo ☑ ☑ GSE 6 Danab ☑ ☑ GSE 7 Meteka ☑ ☑ ☑ 8 Arabi ☑ ☑ GSE 9 Dofan ☑ ☑ ☑ 10 Kone ☑ ☑ ☑ 11 Nazareth ☑ ☑ ☑ 12 Gedemsa ☑ ☑ ☑ 13 Tulu Moye ☑ ☑ - 14 Aluto-2 (Aluto-Finkilo) ☑ ☑ ☑ 15 Aluto-3(Aluto-Bobesa) ☑ ☑ ☑ 16 Abaya ☑ ☑ - (17) Fantale ☑ ☑ - (18) Boseti ☑ ☑ ☑ (19) Corbetti ☑ ☑ - (20) Aluto-1 (Aluto-Langano) ☑ ☑ - (21) Tendaho-1 (Tendaho-Dubti) ☑ ☑ - (22) Tendaho-2 (Tendaho-Ayrobera) ☑ ☑ ☑

(Source: JICA Project Team)

☑:Target for the M/P formulation project GSE: The sites where GSE should undertake the site survey due to access and/or security issues. Source: Proposed by the JICA Project Team based on the R/D (11 June 2013) and subsequent discussions between GSE and the JICA Project Team


S-3

April 2015



2. ELECTRICITY DEVELOPMENT PLAN

2.1 Growth and Transformation Plan The latest government development plan is the Five-year Growth and Transformation Plan (GTP) for

the period 2010/11-2014/15. The strategic directions of the energy sector are development of

renewable energy, expansion of energy infrastructure, and creation of an institutional capacity that

can effectively and efficiently manage such energy sources and infrastructure. The main objective of

the energy sector is to meet the demand for energy in the country by providing sufficient and reliable

power supply that meets international standards at all time. The main targets of the energy sector are

summarized in Table 2.1.

Table 2.1 GTP Targets of the Energy Sector Description of Target 2009/10 2014/15

1. Hydroelectric power generating capacity (MW) 2,000 10,000

2. Total length of distribution lines (Km) 126,038 258,000

3. Total length of rehabilitated distribution lines (Km) 450 8,130

4. Reduce power wastage (%) 11.5 5.6

5. Number of consumers with access to electricity 2,000,000 4,000,000

6. Coverage of electricity services (%) 41 75

7. Total underground power distribution system (Km) 97 150

Source: GTP (2010/11-2014/15)

2.2 Overview of Power Sector

2.2.1 Policy, Laws, Regulations, and Strategy The Plan for Accelerated and Sustained Development to End Poverty (PASDEP) was presented as a

five-year (2005/06-2009/10) development strategy in 2006. Following PASDEP, the GTP mentioned

the current national policy for the period 2010/11 – 2014/15 and has targets to increase the installed

capacity by 8,000 MW of renewable energy resources. Table 2.2 presents the targets of PASDEP and

GTP.

Table 2.2 Targets in the PASDEP/GTP Period 2005-2015

Item 2005/06 PASDEP

2005/06-2009/10 2012

GTP 2010/11-2014/15

Installed Capacity 791MW 2,218 MW (+1,427MW) 2,168 MW 10,000 MW Electrification Rate 16% 50% (+34%) 17% 75% Length of Transmission/Distribution Line

- 13,054km 12,461 km 258,000 km

Electricity Loss 19.5% 13.5% - 5.6%

Source: PASDEP/GTP (summarized by the JICA Project Team)

The Ethiopian Electric Power Corporation (EEPCo), former the national electricity utility in charge

of power generation plan, completed the “Ethiopian Power System Expansion Master Plan” for the

next 25 years (2013–2037) in February 2014.

2.2.2 Power Sector Institutions There are five major institutions engaging in the power sector, namely: (i) Ministry of Mines (MoM),


S-4

April 2015



(ii) Geological Survey of Ethiopia (GSE), (iii) Ministry of Water, Irrigation and Energy (MoWIE),

(iv) Ethiopian Electric Power (EEP) and Ethiopian Power Utility (EEU), and (v) Independent Power

Producers (IPPs). The MoM and MoWIE undertake policy- and regulation-making; while GSE

conducts geothermal exploration, and EEP, EEU, and IPPs undertake construction and operation of

power supply system (generation, transmission and distribution).

2.2.3 Power Demand Forecast The Ethiopian Power System Expansion Master Plan (2014) forecasted that the energy demand

would grow from 1,445 GWh of 2013 to 146,691 GWh in 2037 as shown in Figure 2.1; Energy

export sales are forecast to grow from 1,445 GWh in 2013 to 35,303 GWh by 2037, and the total

demands (MW) of exports are forecast to grow from 140 MW in 2012 to 4,080 MW by 2037.

*Actual record in 2012

Source: Ethiopian Power System Expansion Master Plan, EEPCo, arranged by JICA Project Team

Figure 2.1 Energy Requirement Forecast including Exports (2012-2037)

2.2.4 Power Generation Planning Table 2.3 shows the existing electricity development plan indicated in the EEPCo master plan,

except geothermal power plant.

Ethiopia is blessed with high hydropower potential. In the last five years (2009 – 2013), a total of

1,200 MW of hydropower plants at four sites were put into operation which has made the installed

capacity as triple as the before. The government of Ethiopia intends to continue to develop its

hydro-potential as shown in the Table 2.3.

17,447

45,960

77,343

110,698

135,386146,691

21,490

56,932

97,294

149,902

196,419

221,594

6,90614,393

34,76048,848

68,74279,296 84,803

0

50,000

100,000

150,000

200,000

250,000

2012

*

2013

2014

2015

2016

2017

2018

2019

2020

2021

2022

2023

2024

2025

2026

2027

2028

2029

2030

2031

2032

2033

2034

2035

2036

2037

Reference High LowGWh

Year

Power Generation


S-5

April 2015



Table 2.3 Existing Electricity Development Plan (except geothermal)

Power Plant Status Installed Capacity

(MW) Power Generation

(GWh)

Hydropower Under Construction 8,124 21,826 Candidate 12,407 59,279

Wind Farm Committed 153 424 Candidate 1500 4,765

Solar Candidate 300 526 Biomass Candidate 120 578 Energy from Waste Committed 25 186 Sugar Factory Candidate 474 2,283 Gas Turbine Candidate 280 2208 CCGT Candidate 420 3219 Diesel Candidate 70 515

Source: EEPCo 2014, summarized by the Project Team

2.2.5 Transmission Planning Transmission expansion plan was developed in the EEPCo master plan study based on the demand

forecast and generation plan mentioned above. The transmission expansion plan was considered to

connect the candidate power plants meeting the electrical demand forecast in two stages, i.e.,

short-term from 2013 to 2020 and long-term from 2021 to 2037. This development plan includes the

generation plan of committed geothermal project including Aluto-Langano and Corbetti. Most of the

other geothermal prospects in this project are located along the existing and planned networks which

also run along the Great Rift Valley.

2.2.6 Financing and Tariff Table 2.4 shows the published consumer tariffs in Ethiopia for 50 years from 1959 to 2003. The

domestic tariff is reduced to around ETB 0.47/kWh (equivalent to around USD 0.03/kWh) with a

large amount of subsidies, so that the poverty group can have access to electricity.

Table 2.4 Consumer Tariffs

LV: Low Voltage、HV: High Voltage

Source: Ethiopian Power System Expansion Master Plan, EEPCo, arranged by the JICA Project Team

2.3 Geothermal Power Development

2.3.1 Committed Geothermal Power Development Plans In this master plan study, considering the latest information on donor involvements and GSE plan,

existing and committed geothermal sites are ranked in priority order of development. Table 2.5

summarizes the committed geothermal prospects.

1952-1964 1988-1989 1990 1991-1998 1999-2003EEPCo ICS SCS EEPCo ICS SCS EEPCo ICS SCS EEPCo EEPCo EEPCo EEPCo EEPCo

1 House Hold 0.1250 0.1250 0.1250 0.1250 0.1425 0.1513 0.1468 0.1425 0.1513 0.1468 0.1772 0.2809 0.3897 0.47352 Commercial 0.0750 0.1250 0.1650 0.1436 0.1525 0.1975 0.1735 0.3436 0.4146 0.3774 0.3653 0.4301 0.5511 0.67233 Street　Light 0.1100 0.1500 0.1285 0.1100 0.1500 0.1285 0.3322 0.4146 0.3711 0.3333 0.3087 0.3970 0.48434 Small Industry 0.1333 0.1733 0.1520 0.1333 0.1733 0.1520 0.2232 0.4597 0.32035 LV 0.0475 0.0875 0.0645 0.0625 0.1175 0.0857 0.2232 0.4397 0.3133 0.2563 0.3690 0.4736 0.57786 HV 15kV 0.0288 0.0780 0.0474 0.0588 0.0588 0.2029 0.2029 0.2341 0.2597 0.3349 0.40867 HV 132kV 0.2416 0.3119 0.3805

Total Flat Rate 0.0968 0.0824 0.1241 0.1011 0.1027 0.1556 0.1165 0.2341 0.3500 0.2735 0.2645 0.3086 0.4020 0.4900

1965-1971 1972-1978 1979-1987DescriptionHistorical Flat Tariff Rate (Birr/kWh) EFY


S-6

April 2015



Table 2.5 Committed and Planned Geothermal Prospects MP

S No. Site

Planned Capacity and COD

Status of Commitment

2 Tendaho-3 (Allalobeda)

25 MW 2017 ICEIDA/NDF assists surface survey including MT survey.

19 Corbetti

20 MW 80 MW

200 MW 200 MW

2015 2016 2017 2018

Reykjavík Geothermal (RG)’s PPA: maximum of 1,000 MW in the next 8-10 years. Using GRMF fund, GSE is conducting a study.

20 Aluto-1(Aluto-Langano) 75 MW 2018 The Government of Japan and World Bank has assisted in drilling of wells.

21 Tendaho-1(Dubti) 10 MW 2018 AFD assists in well drilling for 10 MW. Total 610 MW

MP S.No.: Site numbering in this MP study, AFD: French Development Agency

Source: JICA Project Team

2.3.2 Existing Geothermal Development Plans In the EEPCo master plan, all candidate geothermal power plants are sized in multiples of 100 MW

capacities for simplicity without considering the site specific potential and installation plans based

on forecast demand.

Source: Ethiopian Power System Expansion Master Plan, EEPCo

Figure 2.1 Installed Capacity and Reserve Margin

2.3.3 Superiority of Geothermal Power Generation Geothermal power generation will be of the most important energy together with the hydropower in

Ethiopia, from the following reasons.


S-7

April 2015



Energy Security

Energy Mix

Reliable Electrical Supply

Greenhouse Gas Mitigation

Source: JICA Project Team, based on demand curve provided by EEP

Figure 2.2 Schematic Image of Electrical Supply Composition against Electricity Demand in

a day


S-8

April 2015



3. GEOTHERMAL POTENTIAL SURVEY

3.1 Collection of Existing Information

3.1.1 Objective

All the available existing geological papers, articles, and reports were collected for each geothermal

site as the background information for this Project.

3.1.2 Regional Survey Reports

Basic and comprehensive geological investigations were carried out from the early 70s to 80s.

Comprehensive investigations and researches were conducted by the United Nations Development

Programme (UNDP) in 1973, the Ministry of Mines in 1984, and Electroconsul/Geothermica in 1987;

thereby, most of the prospective geothermal areas were determined. As a result, those investigations

summarized that Aluto and Tendaho sites have the highest potential of all the prospective geothermal

sites in Ethiopia.

3.1.3 Detailed Geothermal Survey

Detailed surveys have been conducted since the 1980s at most of the sites. The status of surveys at

each site is shown in Table 3.1.

Table 3.1 Status of Detailed Survey at Each Site

No. Geothermal Sites Geological Survey

Geochemical Survey

Geophysical Prospecting

Other Surveys

1 Dallol ☑ ☑ - 2 Tendaho-3 (Tendaho-Allalobeda) ☑ ☑ ☑ 3 Boina ☑ ☑ - 4 Damali (Lake Abbe) ☑ ☑ - 5 Teo ☑ ☑ - 6 Danab ☑ ☑ - 7 Meteka ☑ ☑ - 8 Arabi - ☑ - 9 Dofan ☑ ☑ -* 10 Kone ☑ - - 11 Nazreth (Boku-Sodole) ☑ ☑ ☑ 12 Gedemsa ☑ ☑ -* TG well 13 Tulu Moye ☑ - - 14 Aluto-2 (Aluto-Finkilo) ☑ ☑ -* TG well 15 Aluto-3 (Aluto-Bobesa) ☑ ☑ -* 16 Abaya ☑ ☑ - 17 Fantale ☑ ☑ - Magnetic Survey 18 Boseti ☑ ☑ - 19 Corbetti ☑ ☑ ☑ 20 Aluto-1 (Aluto-Langano) ☑ ☑ ☑ 21 Tendaho-1 (Tendaho-Dubti) ☑ ☑ ☑ 22 Tendaho-2 (Tendaho-Ayrobera) ☑ ☑ ☑ Radon Survey

☑: done, - : not done, -*: to be done, TG Well: Thermal Gradient well Note: The sites having limited data, are also classified as “done”.



S-9

April 2015



It was confirmed that at least the geological survey and geochemical survey were conducted at each

site. However, the quality and quantity of the results are not unified, e.g., entire site was not covered,

location of geological manifestations was not shown, or location of sampling was not shown.

3.1.4 Feasibility Study

Feasibility (or pre-feasibility) study was conducted at Tendaho-1 (Tendaho-Dubti), Tendaho-2

(Tendaho-Ayrobera), and Aluto-1 (Aluto-Langano) geothermal sites. In 1986,

Electroconsul/Geothermica conducted geothermal reservoir evaluation, design of facilities, and

economical evaluation, by drilling nine wells at Aluto-Langano. In 1996, the Ethiopian Institute of

Geological Survey (former GSE)/Aquater conducted geothermal reservoir evaluation by drilling

three wells at Tendaho-1 (Tendaho-Dubti) and Tendaho-2 (Tendaho-Ayrobera). Afterward, GSE

continued the drilling of three wells by themselves from 1995 to 1998.

3.1.5 Geothermal Plant Construction /Operation and Maintenance

The first geothermal power plant was constructed at Aluto-1 (Aluto-Langano) in 1992, based on the

above feasibility study. Reports were issued for operation and maintenance of geothermal wells after

the power plant construction.

3.2 Satellite Data Analysis

3.2.1 Objectives

Prior to the field survey, alteration zoning, mineral and lithological mapping, topographic

interpretation, and geological structure analysis were carried out using satellite images. Field survey

was conducted based on the results of the satellite data analysis and review of existing reports.

3.2.2 Methodology

Japanese satellite products, ASTER L3A and PALSAR L1.5, were used.

In ASTER data analysis, the band composite image and the band ratio image are created by using

Short Wavelength Infrared (SWIR) bands; thereby distributions of various alteration zones were

detected, rock facies and mineral mapping and interpretation of geological structures were conducted.

In PALSAR data analysis, the mosaic image of geothermal development sites was created; thereby

such geological structures as lineaments/faults, craters, caldera, lava domes and/or lava flows were

identified.

The integrated analysis on GIS was conducted with the results of ASTER DEM data compiled

together with the results of the ASTER and PALSAR data analysis. As the result, the outcrop

distributions of altered rocks were extracted and geological structures were interpreted.


S-10

April 2015



3.2.3 Results

The results of each site are as follows.

All 22 target sites are located in the East African Great Rift Valley,

In all targets sites, a number of major lineaments/faults running parallel to the direction of the

rift valley were identified,

Geothermal sites are in general classified into (1) Volcanic body, (2) Caldera form, and (3)

Graben; distribution of those are more or less parallel to the direction of the rift valley,

Hydrothermal alterations were identified in areas of volcanic bodies and calderas. Intensity

of such alteration varies from site to site; whereas particular alterations were not identified in

Graben areas possibly due to coverage with unconsolidated new sedimentary deposits.

Information obtained from the satellite image analysis was used not only in field to determine the

targets sites to be visited, but also to classify the targets area for reservoir volume estimations.

3.3 Results of the Field Survey and Laboratory Analysis 3.3.1 Geological Survey

(1) Objectives

This site reconnaissance was conducted for the following purposes:

Confirmation of geology (Topography, rocks, structures, and alteration zones: supplemental

survey for existing site survey result);

Confirmation of alteration zones which were determined by remote sensing; and

Collection of samples for rocks and alteration minerals.

(2) Methodology

Site Survey

The site reconnaissance was conducted in two stages. Exact survey points were selected based

on the existing data, remote sensing data, and interview results from local residents. The Dallol

and Arabi areas were investigated by GSE experts only.

Geological Analysis

The samples collected during site reconnaissance were analyzed by x-ray fluorescence (XRF)

for determining rock composition and by X-ray diffraction (XRD) for determining alteration

minerals.


S-11

April 2015



Table 3.2 Methodology of Geological Analysis Type of Samples Analysis Method Objective

Rock Samples XRF Composition of Rock (%) (SiO2, Al2O3, CaO, MgO, Na2O, K2O, Cr2O3, TiO2, MnO, P2O5, SrO, BaO)

Alteration Minerals

Zeolite and Others

XRD (powder specimen) Determination of alteration mineral

Clay Minerals XRD (oriented specimen)

Determination of clay mineral

- Treated by Ethylene Glycol

- Treated by HCl

Identification of clay minerals (Chlorite- Kaolinite, Chlorite- Smectite)


(3) Results

The results of the geological survey are as follows:

1) Site Survey Results

The results of the site reconnaissance were summarized in the following categories.

i) Topography and route map ii) General geology iii) Geological structure, fault, and others

iv) Geothermal manifestation v) Alteration vi) Photos and others

In addition, the sites were grouped in accordance to geological and geo-morphological

characteristics based on the field reconnaissance and the remote sensing analysis as shown in Table

3.3. The results were used for reservoir resource assessment.

Table 3.3 Geological, Geo-morphological Classifications of the Target Area Classification Volcanic body Caldera Graben Target Sites Dallol

Boina Damali Dofan Tulu Moye Aluto Abaya Fantale Boseti

Gedemsa Kone Nazareth Corbetti

Tendaho-Allalobeda Tendaho-Ayrobeda Tendaho-Dubti Teo, Danab Meteka Arabi Butajira


2) Results of Laboratory Analysis (XRF and XRD)

The results of the geological laboratory analysis (XRF and XRD) are shown in Table 3.4. The results

are as follows:

3) Result of XRF Analysis for Rock Composition


S-12

April 2015



SiO2-K2O+Na2O Diagram (TAS Diagram)

Figure 3.1 shows the results of analysis for the project with the results of existing reports

(Electroconsult/Geotermica, 1987; UNDP, 1973).

The results are as follows:

The analyzed data were in good agreement with the data in existing reports, classified as

alkali rock series.

The compositions of trachyte and rhyolite are similar to that of Olkaria of Kenya. Most of

the target sites in Ethiopia are considered to be geologically promising site in the entire

African Rift.

FeO-MgO-K2O+Na2O Diagram

FeO-MgO-K2O+Na2O Diagram is commonly used for the trend of magmatic segregation in

rock series. Figure 3.2 shows the results of analysis for the project with the results of existing

reports. Analyzed data were in good agreement with the data in existing reports. Almost all the

samples showed similar trends to that of tholeiitic series. All the sites are considered to have

similar characteristics such as depth of magma chamber, cooling speed, and others.


Figure 3.1 SiO2-K2O+Na2O Diagram (TAS Diagram)


S-13

April 2015




S-14

April 2015


Figure 3.2 FeO-MgO-K2O+Na2O Diagram

4) Result of XRD Analysis for Alteration Minerals

Table 3.4 shows the results of determination of minerals by XRD.

Table 3.4 Mineral Occurrence by XRD


Rock alteration was observed only around geothermal manifestations. Wider areas of alteration

zone were not identified, except for Dofan and Meteka sites.

Table 3.4 shows that sites are characterized by the occurrence of Quartz, Opal-A, Opal-CT,

Clinoptilorite, Halloysite, Smectite, which suggests that low-grade alteration occurred in those

sites. The occurrence of Kaolinite at Gedemsa and Finkilo sites shows trace of hydrothermal

alteration.

No. Site Location Sample Quartz Opal - CT Opal - A Clinoptilolite Kaolinite Halloysite Smectite

140119-02 Bobesa (Aluto-2) Bobessa Altered Clay △ ＋ 140120-03A Bobesa Bobessa Altered Obsidian ＋－ 140120-03B Bobesa Bobessa Zeolite ＋－ 140120-04 Bobesa Bobessa Altered Rock －＋ 140120-05 Bobesa Bobessa Secondary Mineral ＋ 140120-06 Bobesa Gebiba Clay Mineral ＋ 140121-03 Finkilo (Aluto-3) Finkilo Yellow Tuff －－ 140122-02 Finkilo Adoshe Yellow Clay ＋＋ 140122-03 Finkilo Adoshe Red Clay －－ 140122-04 Finkilo Adoshe White Mineral ○ － 140122-05 Finkilo Humo Clay －＋＋ 140122-06 Finkilo Humo White Mineral ＋ 140122-07 Finkilo Shutie Clay △ ＋ 140122-08 Finkilo Shutie White Mineral △ － 140125-01 Gedemsa Sambo Zeolite Vein －＋＋ 140125-03 Gedemsa Sambo Altered Welded Tuff ○ 140125-04 Gedemsa Sambo White Mineral ○ ＋＋ 140126-01 Nazereth Boko Yellow Tuff △ ○ 140131-03 Boseti Kintano Altered Andesite －－ 140131-04 Boseti Kintano White Mineral ＋＋



3.3.2 Geochemistry –Summary

(1) Objectives

In order to characterize the geothermal reservoirs, site reconnaissance of geothermal manifestations,

sampling and analysis of geothermal fluid and gas, and examination of the analysis results were

conducted. The results of the examination are summarized below.

(2) Methodology

In the site reconnaissance, geothermal manifestations, river, and lake were surveyed at 71 points in

total. At the survey points, location (coordinate), altitude, temperature, pH, and conductivity were

measured, and samples (32 water and 11 gas samples) were collected from 41 points. The survey areas

are as follows:

The second site reconnaissance: Aluto, Bobesa, Finkilo, Gedemsa, Nazreth, Boseti, and Kone

The third site reconnaissance: Dofan, Meteka, Dubti (Tendaho-1), Ayrobeda (Tendaho-2),

Allalobeda (Tendaho-3), Seha, Lake Loma, Boseti (additional survey), Dallol, Arabi, and Erer

(3) Results

Site reconnaissance

The results of the site reconnaissance revealed the facts as below.

In the southwestern part of the Ethiopian Rift Valley, a main geothermal manifestation is fumarole

located in uplands. Fumaroles whose temperature is more than 90°C are located in Aluto, Bobesa, and

Gebiba; only the fumaroles in Gebiba show a boiling temperature in the southwestern part. The other

fumaroles are of lower temperatures (70-90°C) less than a boiling temperature. Hot springs are

distributed mainly in lowlands around Langano Lake and the Nazareth area. Their temperatures are

middle to low, ranging from 65° to 35°C, and boiling spring were not found. Relatively high

temperatures are 65°C of Ouitu (Langano Lake) and 50°C of Sodere (Nazareth).

In the northeastern part of the Ethiopian Rift Valley, fumaroles and hot springs are distributed in

upland and lowland areas. The manifestations show temperatures higher than those in the

southwestern part. Fumaroles with temperatures higher than 90°C are located in Dofan, Dubti,

Ayrobeda. In Dubti and Ayrobeda, temperatures of fumaroles are slightly higher than a boiling

temperature. Hot springs distributed in Dofan, Meteka, Allalobeda, and Seha; there are hot springs

with the temperature higher than 80°C, except for Dofan. A boiling hot spring is located at Allalobeda.

Taking a wide view of the Ethiopian Rift Valley, Aluto-Langano and Tendaho are the remarkable sites

showing prominent activity of geothermal manifestations.


S-15

April 2015



(4) Interpretation of analytical results of samples

Origin of geothermal fluid

Origin of geothermal fluid can be meteoric water as inferred by the isotopic composition of the

geothermal and river/lake waters.

Main anion composition, pH, and isotopic composition of water samples show regional properties in

chemical composition as below.

The geothermal waters in Lake District and Southern Afar are rich in HCO3, on the

contrary, the geothermal waters in Northern Afar are rich in Cl.

In Lake District, the anion composition of the surface water rich in HCO3 is

unchangeable in the geothermal reservoir where the surface water penetrates, and hence

HCO3-rich water can be reservoir water in the southwestern part of the Ethiopian Rift

Valley.

The similarity in the anion composition between geothermal wells and hot springs

indicates that the geothermal fluid taken from Aluto and Langano areas belong to a

single geothermal system.

The geothermal waters in Northern Afar are rich in Cl, and hence similar to those in the

geothermal systems in subduction zones.

The geothermal waters in Tendaho show oxygen shift in the isotopic composition,

which means a progress of water-rock interaction.

The chemistry of Dallol hot spring can be strongly affected by volcanic HCl gas.

(5) Application of geochemical thermometers to geothermal fluid

Na-K-Mg diagram implies that waters from geothermal wells in Tendaho and hot springs in

Allalobeda are fully equilibrated with surrounding rock. On the contrary, waters from geothermal

wells in Aluto and hot springs of Oiutu in Langano are partially equilibrated with surrounding rock

and the other hot spring waters are immature in the state of water-rock interaction.

Comparison among geochemical temperatures and temperatures obtained by well loggings provides

conditions as follows: [1] the quartz thermometer shows a good agreement with well-logging

temperatures of geothermal wells, [2] temperatures calculated with the quartz thermometer converge

within a narrow range in each survey site, so that the quartz temperatures can be recognized as a

representative one of the hot spring aquifer, [3] geochemical temperatures of hot springs, except for

quartz temperatures of Allalobeda, are lower than those of geothermal wells. [4] There is no a single

trend in the orders of temperatures between quartz and Na-K/Na-K-Ca temperatures throughout the all

survey sites.

The conditions above demonstrate that no geochemical temperature of hot spring can directly indicate


S-16

April 2015



plausible reservoir temperature. For this reason, with an assumption where the temperature difference

between the geothermal reservoir and hot spring aquifer is represented by the difference in quartz

temperature between a geothermal well in Aluto and hot springs in Langano, the reservoir

temperatures were estimated by adding the temperature difference to the quartz temperatures of hot

springs for each survey site.

Using the estimated reservoir temperatures and distribution density and activity of geothermal

manifestations, the conditions of the reservoir temperature used in a volumetric method were arranged

in the four classes of temperature ranges: A: 240°C–290°C, B: 210°C–260°C, C: 170°C–220°C, D:

130°C–170°C.

(6) Geochemical properties of fumarolic gas and steam from a geothermal well

Chemical and noble gas isotopic compositions of fumarolic gas and steam from a geothermal well

demonstrate that the origin of the geothermal gas in the Ethiopian Rift Valley is gas emanating from

the mantle. The mantle component in the geothermal gas, thus, can be an indicator of the mantle or the

magma generated from the mantle as the heat source. Furthermore, the movement of the gas indicates

a flow path running from a depth to the surface, that is, a fracture zone. Therefore, it can be said that

the obvious contribution of the mantle component in the geothermal gas indicates a highly potential

geothermal reservoir at a depth.

(7) Verification of analytical precision at GSE

In order to verify the precision of chemical analysis at GSE, GSE and the JICA study team analyzed

shared water samples, and compared the both results. The results and conclusions of the comparison

are as follows.

GSE has sufficient analytical precision for pH, EC (electric conductivity), Cl, SO4,

HCO3, F, Na, and K.

GSE’s results show that insufficient analytical precision for a high concentration of

SiO2. A cause of this issue might be a lack of digesting of polymerized silica in the

process of the analysis.

Because K is an important component used in geochemical thermometers, it is

preferable for GSE to improve the analytical precision of K in high concentration.

GSE's analytical precision is insufficient for Ca and Mg. A solution to this problem is

use of ICP atomic emission spectroscopy.

The top priority in the chemical analysis at the GSE laboratory is to achieve sufficient

analytical precision for a high concentration of SiO2 and K. For this reason, in the

training course for GSE in Japan, engineers were trained in SiO2 measurement with

spectrophotometry, and Na and K with flame atomic emission spectroscopy. These

methods are simple and required apparatus is relatively inexpensive, so that the


S-17

April 2015



employment of these methods is effective in capacity building of the GSE laboratory.

3.4 Preliminary Reservoir Assessment 3.4.1 Objectives

The preliminary geothermal reservoir source assessment was conducted to facilitate the results as

basic information for formulating Master Plan on Geothermal Energy Development.

3.4.2 Definition of Resource and Reserve

For this study, the geothermal resource was described according to the definition of Australian

Geothermal Energy Group Geothermal Code Committee (AGRCC) in the “Geothermal Lexicon for

Resources and Reserves Definition and Reporting Edition 2 (2010)”. This definition is the most

distinct for resource evaluation at the early stage among similar studies according to the International

Energy Agency (IEA)’s comparative study.

The Federal Democratic Republic of Ethiopia’s Scaling-Up Renewable Energy Program Ethiopia

Investment Plan (Draft Final) shows that the planning aspects of geothermal projects consist of eight

stages. The comparison between these eight stages and AGRCC’s categories is shown in Table 3.5.

Table 3.5 Comparison between Eight Stages and AGRCC’s Categories

Eight Development Stages in Ethiopia AGRCC, 2010

Resource Reserve (i) Review of existing information on a prospect

Inferred - (ii) Detailed surface exploration (geology, geochemistry, and

geophysics) (iii) Exploration drilling and testing (minimum of three wells)

Indicated Probable (iv) Appraisal drilling and well testing

(v) Feasibility studies

Measured Proven (vi) Productive drilling, power plant design, EIA, and reservoir

evaluation (vii) Power station construction and commissioning

(viii) Reservoir management and further development


There are no boring holes drilled in the geothermal reservoir in the surveyed sites except Aluto and

Tendaho. Therefore, the geothermal resources of all other sites are classified under “inferred

resources”. On the other hand, Aluto-1 (Aluto-Langano) and Tendaho-1(Tendaho-Dubti) sites are

classified as “indicated resource” and/or “measured resource”.

3.4.3 Methodology of Reservoir Resource Assessment – Volumetric Method

The Volumetric method is used for the reservoir resource assessment. The method was introduced by


S-18

April 2015



USGS (1978) for a rapid assessment. However, the USGS calculation method has appeared not to be

prevailing in references. Instead, an equation, similar to USGS’s in form but different from it in

concept, has been used in many references; therein, unreasonably higher temperatures have been used

as the reference temperature. Instead, the JICA Team herein uses a rational and practical calculation

method for the assessment of reservoir with temperature not less than 180 ºC shown below.

3.4.4 Probabilistic Approach － Monte-Carlo Method

As a probabilistic approach, the Monte Carlo method was used. The software was the Cristal Ball of

Oracle Company. The calculation conditions are given in the table below.

3.4.5 Proposed the parameters

There has not been much information to determine the necessary parameters for the volumetric

method. Hereunder described explanations on how the essential parameters have been proposed for

future reviews as development states should proceed.

(1) Proposal of the reservoir volumes

In most of the target geothermal sites, surface geological and geochemical surveys only were

conducted. Under this circumstance, reservoir volumes were determined with the following

procedures.

The target sites were grouped into three categories (i.e. volcano type, caldera type and graben

type) based on the satellite image analysis and site survey;

Maximum plane area of each site was first determined.

Most likely plane area of each site then was determined with reference to the existing survey

information of Aluto-Langano, Tendaho-Dubti and Corbetti, where MT/TEM survey was

already conducted;

The most likely plane area determined above was adjusted to accommodate field conditions in

accordance with intensity of geothermal manifestations and/or fractures.

Minimum plane area is assumed as zero.

(2) Determination of Reservoir thickness

The parameters shown in the Table 3.6 were assumed.


S-19

April 2015



Table 3.6 Determination of Geothermal Reservoir Thickness

Items Minimum Maximum Most

Probably Notes

Depth to Reservoir top (GL-)

0.5 km 1.0 km 0.8 km Existing information was referred to for “most probably” determination

Depth to Reservoir bottom (GL-)

3.0 km 3.0 km 3.0 km －A depth economically reachable by the present or near future technology

Reservoir Thickness 2.5 km 2.0 km 2.2 km －


(3) Determination of Average Reservoir Temperatures

The reservoir average temperatures were proposed in Table 3.7 based on the geochemical assessment

conducted by the Master Plan Project.

Table 3.7 Average Reservoir Temperatures

Class Min Max Most Probably

Remarks

Class A 240 290 265 6 sites (Tendaho and Aluto) Class B 210 260 235 7 sites (Boseti, Meteka, etc.) Class C 170 220 195 7 sites (Nazareth, Arabi, etc) Class D 130 170 150 2 sites (Gedemsa and Kone)


(4) Geothermal Power Plant Type Assumed

A typical single flash power plant a-is assumed for average reservoir temperature not less than 200 ºC

and binary power plant for average reservoir temperature less than 200 ºC. The Class C geothermal

reservoir includes both temperature categories above 200 ºC and below 200 ºC. For such case, a flash

type power plant was selected from a practical and economical point of view, by assuming that 40% of

the geothermal reservoir would be above 200 ºC. There will be possibilities that double flash type or

Flash/binary combined type may be adopted. However, there are not be sufficient information to

examine such possibilities at this stage; and possible increment due to those option will be minimal

compared to cost impact, thus those examination was not included in this assessment.


Figure 3.3 Average Reservoir Temperature and Power Plant Type

Temperture

Class A

Class B

Class C

Class D

Calculation

100 150 200 250 300

Binary Single Flash

100%

100%

40%

100%


S-20

April 2015



3.4.6 Results of Reservoir Assessment

The assessment results are shown in Table 3.8. The assessment resulted that the most likely value

(‘mode’ in statistic term) is 4,200 MW, value at occurrence probability 80% is 2,000 MW and the

value at occurrence probability 20% is 11,000 MW. There 12 geothermal prospects that may have

resources more than 100 MW.

It is noted that this calculation results provided the resource estimation of “Inferred level” in principle.

However, the total calculation result (91 MW) of Aluto-1 (Aluto-Langano) will include 70 MW of

‘Indicated Resource’ and 5 MW of ‘Measured Resource’; because 70 MW has been estimated by a

numerical simulation and 5 MW is the power output of the pilot plant. Similarly, 10 MW of

(Indicated resource) that was estimated by a Pre-feasibility Study (2014) is included in 290 MW of

Tendaho-1 (Dubti).

Table 3.8 Resource assessment Unit: MW

Target Site

Site No. Cumulative

probability 80% Most Probable

(mode) Cumulative

probability 20% 19 Corbetti 480 960 2400 16 Abaya 390 790 1900 13 Tulu Moye 202 390 1100 18 Boseti 160 320 800 21 Tendaho-1 140 290 660 4 Damali 120 230 760 7 Meteka 61 130 290 2 Tendaho-3 64 120 320

17 Fantale 64 120 320 14 Aluto-2 58 110 290 22 Tendaho-2 47 100 230 3 Boina 56 100 350

20 Aluto-1 49 91 180 9 Dofan 41 86 200

15 Aluto-3 23 50 110 1 Dallol 23 44 120

12 Gedemsa 20 37 100 11 Nazreth 17 33 100 10 Kone 7 14 42 6 Danab 6 11 30 5 Teo 4 9 23 8 Arabi 4 7 36

New/ Divided Site 7-2 Meteka-Ayelu 47 53 250 7-1 Meteka-Amoissa 28 89 150 23 Butajira 6 16 30

Total 2114 4200 10791

Updated After MT/TEM Survey (See Chapter 7)

18 Boseti 175 265 490 22 Tendaho-2 120 180 320



S-21

April 2015



4. ENVIRONMENTAL AND SOCIAL CONSIDERATIONS

4.1 Outline of Environmental and Social Impact Assessment Study

The Environmental and Social Impact Assessment (ESIA) study was conducted to evaluate potential

environmental impacts due to the geothermal energy development at Initial environmental

examination (IEE) level with a comparison of several alternatives.

4.1.1 Objectives of ESIA Study

The main objectives of the ESIA Study are as follows:

To collect natural and social environmental baseline information in order to identify and assess

the potential impacts caused by the Project.

To identify and assess potential impacts on the social/natural environment and pollution caused

by the Project, and

To prepare the management and monitoring plan for necessary actions toward the potential

environmental and social impacts as well as to proposed mitigation measures.

4.1.2 Tasks of ESIA Study

The ESIA Study consists of the following six main tasks.

Baseline survey (collection and compilation of readily available data and information, and

literature review);

Study on alternative plans applying the concept of strategic environment assessment (SEA);

Scoping of the environmental impacts caused by the Project activities;

Prediction and assessment of natural and socio-environmental impacts caused by the Project in

the level of initial environmental examination (pre-IEE);

Mitigation and monitoring plan study; and

Stakeholders’ meeting.

4.2 Environmental Laws and Regulations

4.2.1 Framework of environmental and social laws and regulations

Major Regulations, Guidelines and Proclamations applicable to the geothermal energy development

project are listed in Table 4.1 below.


S-22

April 2015



Table 4.1 Major Regulations, Guidelines and Proclamations No. Title No. Date of Issue 1 Environmental Impact Assessment Proclamation 299 31 Dec, 2002 2 Environmental Pollution Control Proclamation 300 03 Dec, 2002 3 Environmental Protection Organs Establishment Proclamation 295 31 Oct, 2002 4 Expropriation of Landholdings for Public Purposes and Payment of

Compensation Proclamation 455 15 Jul, 2005

5 Rural Land Administration and land Use Proclamation, Proclamation 456 15 Jul, 2005 6 Ethiopian Water Resource Management Proclamation 197 Mar, 2000 7 Solid Waste Management Proclamation 513 12 Feb, 2007 8 Environmental Impact Assessment Procedural Guideline Series 1 Nov, 2003 9 Draft EMP for the Identified Sectoral Developments in the Ethiopian

Sustainable Development & Poverty Reduction (ESDPRP) 01 May, 2004

10 Investment Proclamation 280 02 Jul, 2002 11 Council of Ministers Regulations on Investment Incentives and

Investment Areas Reserved for Domestic Investors 84 07 Feb, 2003

12 The FDRE Proclamation, “Payment of Compensation for Property Situated on Landholdins Expropriated for Public Purposes”

455 2005

13 Council of Ministers Regulation, “Payment of Compensation for Property Situated on Landholdins Expropriated for Public Purposes”

135 2007

14 Oromia Regional Administration Council Directives, “Payment of Compensation for Property Situated on Landholdins Expropriated for Public Purposes”

5 2003

15 Investment (Amendment) Proclamation 373 Oct, 2003


4.2.2 Environmental Impact Assessment

(1) Laws and regulations relating to EIA in Ethiopia

According to the EIA Procedural Guideline, projects are categorized into three schedules:

Schedule-1: Projects, which may have adverse and significant environmental impacts and therefore

require a full Environmental Impact Assessment.

Schedule-2: Projects whose type, scale or other relevant characteristics have potential to cause some

significant environmental impacts but are not likely to warrant a full EIA study.

Schedule-3: Projects which would have no impact and do not require an EIA.

Projects for geothermal power plant fall under the schedule I activities.

(2) EIA Process

The general description of the EIA process and the permit requirements are detailed in the EIA

Procedural Guideline Series 1 of the FDRE. As a minimum, the following descriptions shall be

presented:

the nature of the project, including the technology and processes to be used and their physical

impacts;

the content and amount of pollutants that will be released during implementation as well as

during operation;

source and amount of energy required for operation;


S-23

April 2015



characteristics and duration of all the estimated direct or indirect, positive or negative impacts

on living things and the physical environment;

measures proposed to eliminate, minimize, or mitigate negative impacts;

a contingency plan in case of accidents;

Procedures of internal monitoring and auditing during implementation and operation.

Environment related standards and Limit Values

The following standard and limit values were indentified for an application to geothermal energy

development projects.

Draft Standards for Industrial Emission and Effluent Limits (Ethiopian EPA)

National Noise Standard at Noise Sensitive Areas

Environmental, Health and Safety (EHS) Guidelines for Emission Gas (World Bank)

EHS Guidelines for Effluent (World Bank)

EHS Guidelines for Noise Management (World Bank)

(3) Legislation related to the resettlement and land acquisition

Constitution (1995) assure right of private property for citizen but not land ownership. The land is

recognized as public common property and its usufruct right can be processed, sold and transferred by

citizens. “Federal Democratic Republic of Ethiopia Rural Land Administration and land Use

Proclamation, Proclamation No.456/2005” provides the rural land use right. The law also prescribes

the governmental responsibility that regional government have obligation to organize adequate

legislative administration under the central governmental policy.

Principle of the land acquisition for the public purpose is provided in the constitution (1995) and the

detail procedure such as expropriation process and compensation standard are prescribed in “the

Expropriation of Landholding for Public Purposes and Payment of Compensation Proclamation,

Proclamation No. 455/2005”. “Payment of Compensation for Property Situated on Landholdings

Expropriated for Public Purposes, Council Ministers Regulation No. 135/2007” also provides further

detail standard such as compensation standard for the each expropriating asset. According to the

regulation (2007), land expropriation is implemented by local government, Woreda or Urban

administration exclusively for the public purpose and it should be adequately compensated to PAPs.

(4) Gaps between Ethiopian Legislations and JICA Guidelines (2010) Policies on Environmental Assessment

The JICA Environmental guidelines and the legislation in the country do not have major contradiction,

except perhaps certain procedural adjustments during project implementation such as public

consultation and public disclosure.


S-24

April 2015

The Project for Formulating Master Planon Development of Geothermal Energy in Ethiopia

Executive SummaryFinal Report

4.2.3 Institutional Framework of Environmental Management in Ethiopia

The most important step in setting up the legal framework for the environmental in Ethiopia has been

the establishment of the Environmental Protection Authority (EPA). The EPA, established under the

proclamation no. 295/2002, is now a ministerial level environmental regulatory and monitoring body.

The objectives of the EPA are to formulate policies, strategies, laws and standards. It is, therefore, the

responsibility of the EPA. in the EIA process.

The proposed geothermal power plants are subject to several policies and programs aimed at

development and environmental protection. The EPA regulates the environmental management

system for all projects across the country. Following shows the major institutions or organizations.

Regional Government

The Geological Survey of Ethiopia (GSE)

Ministry of Water and Energy (MoWE)

Ethiopian Electric Power Corporation (EEPCo)

Pastoralist and Agricultural and Rural Development Office of Regional State

Corporate Planning Department of EEP

4.3 Baseline Survey

4.3.1 Methodology of Baseline survey

Standard methodologies to collect data and information at the prospective geothermal energy

development sites were applied.

4.3.2 The Baseline data

As the baseline, following data were collected.

Profile of the Study Area

Natural, Historical and Cultural Heritages

Ecological Protected Area

Possible Impacts by Transmission Line

4.4 Strategic Environmental Assessment (SEA)

Although implementation of SEA for development projects is not compulsory at present in Ethiopia,

considering the definition and the concept of SEA mentioned above, SEA for geothermal energy

projects were discussed in this report in the following point of views.

Ethiopian energy policy on geothermal development,Conservation strategy of Ethiopia (CSE)

Environmental Policy of Ethiopia (EPE)

Nippon Koei Co., Ltd.JMC Geothermal Engineering Co., Ltd Sumiko Resources Exploration & Development Co., Ltd.

S-25 April 2015



National Energy Development Policy

Project alternatives including “do-nothing” optionEnergy Resource Alternatives

Project Alternatives

Project perspective from guidelines of financial institutions,

Alignment of JICA guidelines with national policies

4.5 Implementation of IEE

An Initial Environmental Examination (IEE) was carried out based on the baseline data and

information, namely readily available information including existing data and simple field surveys.

4.5.1 Project Categorization

(1) General

According to the JICA Environmental Guidelines (April 2010), projects are classified into four

categories. Table 4.2 below shows the comparison of projects categorization defined by JICA and

Ethiopian national EPA Guideline.

Table 4.2 Environmental Categorization of Projects

Project type JICA GuidelinesEthiopia EPA

GuidelineEIA requirement

Likely to have significant adverse impacts on the environment and society. Projects with complicated or unprecedented impacts that are difficult to assess, or projects with a wide range of impacts or irreversible impacts

Category A Schedule-1 Full EIA

Have potential adverse impacts on the environment and society are less adverse than those of Category A projects. Generally, they are site-specific; few if any are irreversible; and in most cases, normal mitigation measures can be designed more read

Category B Schedule-2Not likely to warrant

a full EIA study

Have are likely to have minimal or little adverse impact on the environment and society.

Category C Schedule-3

Environmental review will not proceed after categorization

Projects which satisfy the following JICA’s requirements: projects of JICA’s funding to a financial intermediary or executing agency; the selection and appraisal of the sub-projects is substantially undertaken by such an institution only after JICA’s approval of the funding, so that the sub-projects cannot be specified prior to JICA’s approval of funding (or project appraisal); and those sub-projects are expected to have a potential impact on the environment.

Category FI -Environmental

review will proceed after categorization

(Source: JICA Study Team)

(2) Classification of geothermal energy development project

Appendix I (Schedule of Activities) of the Environmental Impact Assessment Guideline Document

(May 2000) classifies projects by their type of activities. Based on the project classification,


S-26 April 2015



geothermal energy development projects with capacities more than 25 MW require the

implementation of full scale EIA.

4.5.2 Scoping for Initial Environmental Examination

Geothermal energy is generally more environmentally sound compare to other energy sources such

as fossil fuel burnings, there are certain negative impacts that must be considered and managed when

geothermal energy is to be developed.

Most of potentially important impacts of geothermal power plant development are associated with

groundwater use and contamination, and with related concerns about land subsidence and induced

seismicity as a result of water injection and production into and out of a fractured reservoir

formation. Some considerations should also be taken for issues of air pollution, noise, safety, and

land use.

4.5.3 Socio-environmental Interactions

In order to grasp the livelihood conditions in and around the prospective sites, questionnaire surveys

for energy and water sector offices at woreda levels were conducted.

The survey revealed that the main source of energy both for cooking and light was fuel wood, coal

and dung. In addition to this, energy consumption per capita of the community is very low.

With regard to water source and supply, there is critical shortage of sufficient and uninterrupted

water supply. But in all other sites, access to potable (treated) water is still a priority. There seemed

to be water resource competition and fast land use change in some of the surveyed areas. The finding

revealed that the community believed the project would bring about little negative impact. However

in terms of the serious shortage of water all community in all sites required the supply of water. Thus

there is a strong need of residents to implement community projects to access potable water source,

parallel to the main geothermal project.

4.5.4 Displacement and Resettlement

The scale of geothermal energy development project is not yet determined at present, some of the

areas within the prospective sites shall be acquired by the project proponent for implementation of the

project. Data and Information on land clam were collected through interviews at kebele level in the

prospective sites. After the determination of the project site and the project scale, detailed land

boundary should be settled according to the land acquisition procedure of the government of Ethiopia.


S-27

April 2015



4.6 Environmental Management Plan

4.6.1 Environmental Management Plan (EMP)

Environmental Management Plan (EMP) is prepared on the basis of identified impacts and their level

of significance. Significant impacts that are detailed in the previous section shall be mitigated through

appropriate methods and then subject to mechanisms of environmental management plan using

monitoring and auditing as instrument.

4.6.2 Monitoring plan

Environmental monitoring plan is included in the EMP. Environmental monitoring and auditing shall

be undertaken in all phases of project activities to check that the proposed environmental management

measures are being satisfactorily implemented and that they are delivering appropriate level of

environmental performances. A general form of monitoring plan to be applied to the prospective sites

was given in this report.

4.7 Consultation with stakeholder

Stakeholder Consultations were implemented in the ESIA Study, namely at scoping stage, through

the interviews at communities (March –July 2014).

Consultation with stakeholder at the prospective sites had been conducted through interview and using

questionnaires. Interview and questionnaire surveys had been conducted at seven woreda-level sector

offices, and more than 100 officials from different sectors were participated. In order to remove the

issues and concerns of the community, due regards and detailed explanations were given to the

community based on the legal, social and environmental land regulations stated in the proclamation of

Federal Republic of Ethiopia No. 1/1995..

4.8 Recommendation6

Geothermal energy development projects with a capacity more than 25 MW shall require the

implementation of full scale EIA prior to the implementation of the project. The EIA process consists

of series of several procedural phases starting from pre-screening consultation with EPC and

submission of a screening report and ending up by obtaining an EIA approval. The project proponent

should start the EIA procedures in cooperation with other sectoral agencies such as Ministry of

Water, Irrigation and Energy (MoWIE), regional governments, etc. For the implementation of the

EIA, followings should be noted:

EIA should be conducted in accordance with the Ethiopian EIA process.

EIA should be carried out for the selected site by the project proponent according to the

Ethiopian Guidelines and/or international requirements.


S-28

April 2015



After the determination of the project site(s), EIA should start prior to the test drillings, and

continuously conducted parallel to the test drilling.

The EIA report prepared based on above shall be revised considering the results of the test

drilling above. Results of ESIA survey conducted in this master plan study can be utilized for

the implementation of the EIA

Additional EIA should be conducted if necessary according to the revised EIA report.

The EIA is to be conducted considering the specific features of environmental impacts of

geothermal energy development.

EIA approval should be obtained before the application of the development right of the project.


S-29

April 2015



5. FORMULATION OF MASTER PLAN

5.1 Target and Methodology

The master plan was formulated by first setting out the development targets and then by prioritizing

the identified candidate projects to meet the targets set out.

5.1.1 Target of the Master Plan

Table 5.1 gives the development targets for this master plan.

Table 5.1 Development Target of the Master Plan Item Target Remarks

Period

2015–2037 (23 years) Short term: 2015-2018 (4 years) Medium term: 2019-2025 (7 years) Long term: 2026-2037 (12 years)

EEP MP: 2013–2037 (25 years) Wind and Solar MP: 2011–2020 (10 years)

Installed Capacity Short term 700 MW Committed and ongoing sites Medium term 1,200 MW Same target as EEP MP Long term 5,000 MW Same target as EEP MP

MP: Master Plan Source: JICA Project Team

5.1.2 Methodology of the Master Plan

Five criteria are used: (i) development status, (ii) environmental risks, (iii) geothermal potential, (iv)

economics, and (v) site specific factors.

5.2 Multi-Criteria Analysis for Prioritizing the Geological Prospects

5.2.1 Factors to be Considered

(1) Development Status

Using the Australian Geothermal Reporting Code Committee classification, reliability of geothermal

resource evaluation was classified.

Table 5.2 below shows the classification of geothermal resources. Aluto-1 (Aluto-Langano) and

Tendaho-1 (Dubti), where some test drillings were already done, are evaluated as “measured” and

“indicated” resource, respectively. Other sites where any detailed exploration surveys have yet to be

done are evaluated as inferred resource.

(2) Socio-environmental Impact

According to the environmental and social consideration, Fantale geothermal prospect is located

in/around the Awash National Park. For this reason, Fantale prospect is given a low priority in the

ranking. The other 21 geothermal sites are not located in the range of the national park and do not

have immitigable adverse environmental risks and impacts.


S-30

April 2015



(3) Geothermal Potential

In this study, the installed capacity of each power plant is set as equal to the geothermal potential (at

the most probable case) in each prospect except Aluto-1 (Aluto-Langano). Other donors of a private

firm have started development and drilling surveys of some of the prospects, such as Corbetti,

Aluto-1 (Aluto-Langano), and Tendaho-1 (Dubti). Kone and Gedemsa where the estimated

temperature were as low as 130~170 °C (based on the geochemical analysis), were suitable only for

binary-type generation. Therefore, Kone and Gedemsa prospects were placed at a lower priority due

to extremely low power output with higher energy cost.

Table 5.2 Development Status and Geothermal Resource

Site Temperature

Class Geothermal Resource

Inferred Indicated Measured 1 Dallol B 44 N/A N/A 2 Tendaho-3 (Allalobeda) A 120 N/A N/A 3 Boina C 100 N/A N/A 4 Damali C 230 N/A N/A 5 Teo B 9 N/A N/A 6 Danab B 11 N/A N/A 7 Meteka B 130 N/A N/A 8 Arabi C 7 N/A N/A 9 Dofan B 86 N/A N/A 10 Kone D 14 N/A N/A 11 Nazareth C 33 N/A N/A 12 Gedemsa D 37 N/A N/A 13 Tulu Moye C 390 N/A N/A 14 Aluto-2 (Finkilo) A 110 N/A N/A 15 Aluto-3 (Bobessa) A 50 N/A N/A 16 Abaya B 790 N/A N/A 17 Fantale C 120 N/A N/A 18 Boseti B 265 N/A N/A 19 Corbetti B 1000*1 N/A N/A 20 Aluto-1 (Aluto-Langano) A 16 70*2 5 21 Tendaho-1 (Dubti) A 280 10*3 N/A 22 Tendaho-2 (Ayrobera) A 180 N/A N/A

N/A: Not available *1 Reykjavík Geothermal *2 Study on Geothermal Power Development Project in the Aluto Langano Field, Ethiopia, METI (Japan), 2010, *3 Consultancy Services for Tendaho Geothermal Resources Development feasibility Study, ELC, 2013


(4) Economics of Candidate Plants

The project economics are measured by two indicators: (i) generation cost and (ii) economic

viability.

Cost of Electricity Generation

To compare the competing power plants (geothermal, hydropower and other plant types), the

electricity generation costs (cost of generation) per kWh are calculated.

The results are shown in Table 5.3 below.


S-31

April 2015



Table 5.3 Ranking Order of the Geothermal Prospects


Figure 5.1 and Figure 5.2 compares the generation costs of geothermal and hydropower, and

geothermal and other power plants respectively.

Generally, the generation cost of hydropower is lower than that of geothermal power plants.

However, some geothermal power plants are much more competitive and are more reasonable than

some candidate hydropower plants with similar capacity. In comparison with other renewable energy

and thermal power plants, the geothermal prospects ranked No.1 to No.11 in Table 5.3 are superior to

even Adama and Ashegoda wind farm that exceeds US$0.08/kWh.

Therefore, from the point of view of least cost generation, geothermal must be prioritized over wind

and solar in Ethiopia. The geothermal prospects with generation cost of US$0.10/kWh are almost

equal to wind and solar and more economical than gas turbine and diesel. The diesel generation and

waste from energy are much more expensive than the geothermal prospects.

RankingOrder

Geothermal SiteTemp.Class

InstalledCapacity

(MW)

Cost of Genaration

($/kWh)Remarks

1 Tendaho-1(Dubti) A 290 0.0572 Shallow reservoir is committed.2 Aluto-2 (Finkilo) A 110 0.05853 Corbetti B 1,000 0.0589 Committed site4 Aluto-3 (Bobesa) A 50 0.05925 Tendaho-2 (Ayrobera) A 180 0.05936 Tendaho-3 (Allalobeda) A 120 0.0621 Committed site7 Aluto-1 (Langano) A 75 0.0700 Committed site8 Abaya B 790 0.07179 Boseti B 265 0.072110 Meteka B 130 0.073111 Dofan B 86 0.0783

12 Tulu Moye C 390 0.1037

13 Teo B 9 0.104014 Fantale C 120 0.105015 Dallol B 44 0.107616 Damali C 230 0.108417 Nazareth C 33 0.109118 Boina C 100 0.1111

19 Danab B 11 0.1700

20 Arabi C 7 0.1872- Gedemsa D 37 - Low temperature- Kone D 14 - Low temperature


S-32

April 2015




Figure 5.1 Generation Cost of Geothermal and Hydropower Plants


Figure 5.2 Generation Cost of Geothermal and Other Power Plants If the Government of Ethiopia adopts preferential policy such as advantageous interest rate to

promote geothermal development, geothermal is expected to become more competitive.

Economic Viability

The economic viability of a geothermal plant is evaluated using the economic internal rate of return

(EIRR). The EIRRs are given in Table 5.2. Out of 18 projects, 16 are economically viable since the

EIRRs are more than the hurdle rate of 10%. Two projects (Danab and Arabi) are not economically

viable.

0.0000

0.0500

0.1000

0.1500

0.2000

0.2500

0.3000

0 100 200 300 400 500 600 700 800 900 1000

Ene

rgy

Cos

t ($

/kW

h)

Installed Capacity (MW)

Geothermal Site Wind Farm

Solar Energy from Waste

Biomass Gas Turbine

Diesel (HFO) CCGT

CandidateHydropower Plant

Aluto-Langano

Abaya

Corbetti

Meteka BosetiTulu Moye

Dubti

Damali

Allalobeda

Finkilo

Ayrobera

Bobesa

Dofan

Arabi

Wind

Solar

Energy from Waste

CCGT

Diesel (HFO)

Gas Turbine

Candidate Hydropower

Boina

Teo

0.0000

0.0500

0.1000

0.1500

0.2000

0.2500

0.3000

0 100 200 300 400 500 600 700 800 900 1000

Cos

t of G

ener

atio

n (

$/kW

h)




Biomass Gas Turbine

Diesel (HFO) CCGT

Aluto-Langano

Abaya

Corbetti

Meteka Boseti

Tulu Moye

Dubti

Damali

Allalobeda

Finkilo Ayrobera

Bobesa

DofanWind-Ashegoda

Wind-AdamaSolar

Energy from Waste

CCGT

Diesel (HFO)

Gas Turbine

Boina

Teo

Danab

Arabi


S-33

April 2015



Table 5.4 Ranking of Geothermal Power Plants and EIRR


(5) Site Specific Factors

i) Socio-environmental Impact

Social and environmental impact, except for national park, is taken into consideration for the

prioritization. In addition, it was judged that there would be a potential conflict with local

people in the Dofan prospect. Therefore, Dofan was adjusted to be ranked below the level of the

economy group.

ii) Accessibility to the Sites

Taking into consideration the topography along the access road as well as for security measures,

cost of civil works for the access road and earthworks in the site was estimated as preparatory

work in the construction cost mentioned above. Because the poor accessibility reflects the

generation cost, prospects located in remote areas such as Damali and Danab are evaluated low

in the rank order of the generation cost.

5.2.2 Prioritization of the Geothermal Prospects

To sum up the prioritization of geothermal prospects using multi-criteria analysis mentioned above,

the prioritization order is summarized as shown in Table 5.5.

RankingOrder

Geothermal SiteInstalledCapacity

(MW)

Cost ofGenaration ($/kWh)

EIRR(%)

1 Tendaho-1(Dubti) 290 0.0572 31.7%

2 Aluto-2 (Finkilo) 110 0.0585 31.1%

3 Corbetti 1,000 0.0589 -

4 Aluto-3 (Bobesa) 50 0.0592 30.7%

5 Tendaho-2 (Ayrobera) 180 0.0593 30.8%

6 Tendaho-3 (Allalobeda) 95 0.0621 29.1%

7 Aluto-1 (Langano) 75 0.0700 -

8 Abaya 790 0.0717 25.2%

9 Boseti 265 0.0721 25.0%

10 Meteka 130 0.0731 24.7%

11 Dofan 86 0.0783 23.1%

12 Tulu Moye 390 0.1037 17.0%

13 Teo 9 0.1040 17.4%

14 Fantale 120 0.1050 16.7%

15 Dallol 44 0.1076 16.6%

16 Damali 230 0.1084 16.2%

17 Nazareth 33 0.1091 16.2%

18 Boina 100 0.1111 15.8%

19 Danab 11 0.1700 9.9%

20 Arabi 7 0.1872 8.7%

- Gedemsa 37 - -

- Kone 14 - -


S-34

April 2015



Table 5.5 Prioritization Order of the Geothermal Prospects


5.3 Implementation Plan

5.3.1 General Consideration

Development process of geothermal power plant before the start of generation consists of nine

stages: (i) preliminary survey, (ii) exploration, (iii) appraisal drilling and well testing, (iv) Feasibility

survey, (v) environmental impact assessment, (vi) well/power plant design, (vii) well drilling, (viii)

power station construction and (ix) start-up and commissioning. Taking into consideration the

various development status, which may allow omitting the preliminary survey and exploration,

development plans for each prospect with respect to the fastest case are discussed in the next section

based on the model case above.

5.3.2 Development Plan

Table 5.6 shows overall schedule of geothermal power development taking into account the fastest

case discussed in previous section.

RankingOrder

Geothermal SiteInstalled Capacity

(MW)

Priority-S: Committed Project COD Donor

S Tendaho-3 (Allalobeda ) 25 2017 WBS Corbetti 500 2018 RGS Aluto-1 (Langano) 70 2018 Japan/WB

S Tendaho-1 (Dubti)-Shallow reservoir 10 2018 AFD

Priority-A: Very High Economy Energy Cost (US$/kWh)

1 Tendaho-1 (Dubti)-Deep reservoir 280 0.0572 Deep reservoir

2 Aluto-2 (Finkilo) 110 0.05853 Aluto-3 (Bobesa) 50 0.05924 Tendaho-2 (Ayrobera) 180 0.05935 Tendaho-3 (Allalobeda) 95 0.0621 Expantion

Priority-B: High Economy Energy Cost (US$/kWh)

6 Abaya 790 0.0717 RG has license7 Boseti 265 0.07218 Meteka 130 0.0731

Priority-C: Low Economy Energy Cost (US$/kWh)

9 Tulu Moye 156 0.1037 RG has license10 Teo 9 0.104011 Damali 92 0.108412 Nazareth 13.2 0.109113 Boina 40 0.111114 Dofan 86 0.0783 Conflict with residents15 Dallol 44 0.1076 Difficult due to low pH

Priority-D: Less Feasible Energy Cost (US$/kWh)

16 Danab 11 0.1700 Poor access17 Arabi 2.8 0.1872 Poor accessD Gedemsa 37 - Low temperatureD Kone 14 - Low temperatureD Fantale 48 - Overlapped with national park

Remarks


S-35

April 2015



Table 5.6 Overall Schedule of Geothermal Power Development


Short-term (2014–2018)

From 2015 to 2018, a total output of 610 MW from the geothermal power plants will be developed

in the short-term in this master plan.

The committed geothermal power plants and large-scale hydropower plants under construction, such

as the grand renaissance dam, are expected to generate much more electricity than the forecasted

electricity demand in the short-term. Therefore, some of other power plants generated with other

sources could be implemented in a later stage than planed in EEP master plan as explained below

Medium-term (2019–2025)

According to economic evaluation, the Priority-A and -B prospects are more economical than other

power generation schemes such as wind farms and solar power. Therefore, their development should

be prioritized over other power generation schemes in terms of least-cost power generation plan.

EEP master plan has an expected total of 1,200 MW from wind farms and solar power generation

which are not specified projects in the short-term up to 2018. The JICA Project Team would like to

propose that wind farms and solar power generation projects that are not specified should be delayed

and construction of geothermal power plants, which are mainly planned in the long-term, should be

moved forward instead.

Long-term (2026–2037)

Since most of the hydropower potential in Ethiopia is expected to be developed in the long-term and

electricity demand is forecasted to exceed 20,000 MW in the early 2030s, more geothermal potential

is anticipated to be developed. In this master plan, all geothermal potential 4,100 MW is planned to

14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37

◎

◎

◎

◎

◎

◎

◎

◎

◎

Lisenced by RG ◎

Lisenced by RG ◎

◎

◎

◎

◎

◎

◎

◎

◎

◎

◎

◎

◎

◎

◎

◎: Commencement of Operation

15

16

17

-

-

-

10

9

12

11

13

14

5

-

6

7

8

S

-

1

2

3

4

Short-term Medium-term Long-term

S

S

S

2018

-

-

total

-

3701

Sub-total

2400 -

691 -

-

0.1047

2036

-

-

0.0726

0.1019

0.1643

0.1907

0.0731

0.0971

0.0974

0.1017

0.1017

Sub-total

Sub-total -

-

-

0.0572

0.0585

0.0717

0.0592

0.0609

0.0624

0.0585

0.0720

2036

2027

2027

2029

2029

2029

2030

2030

2036

2036

44

11

7

37

14 2036

-

120

9

390

33

230

100

86

2024

110

50

180

95

500

790

265

130

2021

2021

2021

2022

2024

2024

RankingOrder

Cost ofGeneration(US$/kWh)

25 2017

500

Kone

Fantale

Year of 20**

CODInstalledCapacity

(MW)Prospect

75 2018

10 2018

Boina

Dofan

Dallol

Danab

Arabi

Gedemsa

Boseti

Meteka

Teo

Tulumoya

Nazareth

Damali

Aluto-3

Tendaho-2

Tendaho-3

Corbetti

Abaya

Tendaho-3

Corbetti

Aluto-1

Tendaho-1

Tendaho-1

Aluto-2

25 610 610

280 2020

2020

610 610 610 610 610 610 610 610 610 610 610 610 610 610 610 610 610 610 610

25 610 610 1000 1325 1825 3902 39021825 3010 3010 3010 3409 3409

2400 2400

3772 3902 3902 3902

2400 2400 2400 2400 2400 2400

3902 4091 4091

390 715 1215 1215 2400

892 892

2400 2400 2400 2400

892 1081 1081

2400

399 399 762 892 892 892


S-36

April 2015



be developed by 2037.

5.4 Financial Considerations for Geothermal Development

There will be four possible sources of funds: Word Bank ODA loans, Japan's ODA loan, commercial

banks loans and bonds issue. Their financing conditions (interest rates and repayment periods) are

summarized in Table 5.7.

Figure 5.3 shows the comparison with capital costs of each condition and existing power price

(consumer price). It is concluded that concessional public loans such as Japan’s ODA and/or WB

loans should be utilized to construct geothermal power plants.

Table 5.7 Possible Funds Loan ConditionsItem ODA-WB ODA-GOJ Commercial Banks Bonds

Interest (%) 5.0 3.0 6.0 5.0

Repayment period (year) 20 30 10 7

Source: IDA

Source: JICA Project Team (Fund procurement condition is referred to IDA)

Figure 5.3 Tariff and Production Cost using Several Funds

5.5 Implementation Structure

The energy cost of geothermal power generation shall be below the presently adopted electricity

retail tariffs under the conditions of the present energy price policy.

0.0000

0.0500

0.1000

0.1500

0.2000

0.2500

0.3000

0.3500

Tendaho-1(D

ubti)

Aluto-2 (Finkilo)

Corbetti

Aluto-3 (B

obesa)

Tendaho-2

(Ayrobera)

Tendaho-3

(Allalobeda)

Aluto-1 (L

angano)

Abaya

Boseti

Meteka

Dofan

Teo

Tulu M

oye

Fantale

Nazareth

Dam

ali

Dallol

Boina

Danab

Arabi

Tar

iff

(US

$/kW

h)

Production Costusing ODA-WB

Production Cost using Commercial

Production Cost using Bonds

Production Cost using ODA-GOJ

Domestic Tariff:2.8 cents/kWh

Export Tariff:7.0 cents/kWh

Priority -APriority -B

Priority -C

Priority -D


S-37 April 2015



A case study was conducted where four value chain models were assumed with tariff variation for

each case. Tariffs here are defined as the sales tariffs charged for the electricity generated by the

geothermal power plant at the delivery point to off-takers (Figure 5.4). With the current tariff levels,

possible and sustainable options are a fully public model for the domestic supply project, and

Models C or D for the export supply project.

Source: IFC

Figure 5.4 PPP Model Options and Tariff

The Project Team recommended establishing a new public enterprise EEGeD (Ethiopian Enterprise

for Geothermal Energy Development) by merging the geothermal relevant organizations in GES and

EEP.

Plantconstruction

Fielddevelopment

F/S &planning

Testdrilling

Exploration

PreliminarySurvey

Operation

Field Plant

Public Private

Public Private

Public Private

Public Private

Public

Public Private

Tariff($/kWh) Remarks

0.15

0.13

0.10

0.05

0.03

Corebetti

Tendaho

AlutoLangano

A

B

C

D

FullPublic

Busi

ness

Mod

el


S-38

April 2015



6. GEOPHYSICAL SURVEY

6.1 Purpose At two selected geothermal sites, the geophysical survey was conducted to contribute to the creation

and estimation of geothermal reservoir model and the planning of test drilling survey.

6.2 Selection of the Sites The master plan presented in the section 5 nominated three priority sites, Tendaho-2 (Ayrobera),

Boseti and Meteka, as green fields for development. Among those, we selected Tendaho-2

(Ayrobera) and Boseti for the geophysical survey under the master plan project. It is expected that

GSE will undertake the geophysical survey in Meteka with equipment and training provided by

JICA

6.3 Outline of Methodology At the project, MT/TEM survey was conducted. The outline of methodology is described below.

6.3.1 Survey Method MT method with far remote reference site

TEM method with central loop system（for static correction of MT data）

6.3.2 Number of stations The number of survey stations and the locations of the remote reference are given in Table 6.1.

Table 6.1 Number of survey stations and location of remote reference station

Survey site Stations location of remote reference station

Remarks

Tendaho-2 (Ayrobera) 24 Mille Adding the existing 81 stations for data analysis

Boseti 30 Koka -


6.3.3 Acquired data The acquired data were as follows.

Table 6.2 Acquired data of geophysical survey Survey method Acquired data Remarks

MT method Time series data 3 components in magnetic field (Hx, Hy, Hz) 2 components in electric field (Ex, Ey)

Measurement time: more than 14 hour per one station

TEM method Transient response 1 component in magnetic field (Hz)

-



S-39

April 2015



6.4 Survey results The panel diagrams of the resistivity plan map created on the basis of the results of MT/TEM survey at

Tendaho-2 (Ayrobera) site and Boseti site are shown in Figure 6.1. The resistivity structures are

described below.

6.4.1 Tendaho-2 (Ayrobera) site Generally the resistivity structure composed of three zones namely conductive overburden,

resistive zone and conductive zone at depth from surface to -5,000 m elevation. The resistivity

distribution is roughly in the range of 1 ohm-m to 250 ohm-m.

The conductive belt of NW-SE direction distributes from -700 m elevation to the deep zone and

composes the channel structure of low resistivity in the center of the site. That channel structure

shows the strike direction of the resistivity structure clearly.

The resistivity variation between the channel structure composed by the distribution of low

resistivity and the distribution of high resistivity at the outside of the channel structure is steep

and indicates resistivity discontinuity.

The channel structure of low resistivity is rather narrow in width and shows a little constriction

characteristically around profile TDO97. This characteristic suggests the resistivity

discontinuity across the channel structure.

6.4.2 Boseti site Generally the resistivity structure composed of three zones namely resistive overburden,

conductive zone and resistive zone at depth from surface to -3,000 m elevation. The resistivity


The distribution of the conductive belt of NNE-SSW direction continues form 500 m elevation

to the deep zone and composes the channel structure of low resistivity in the center of the site.

That channel structure shows the strike direction of the resistivity structure clearly.

The resistivity variation between the channel structure composed by the distribution of low

resistivity and the distribution of high resistivity at the outside of the channel structure is steep

and indicates the resistivity discontinuity.

The distribution of low resistivity under the highland in the northern slope of Mt. Bericha

continues from shallow zone to deeper zone. At 1,200 m elevation, the high contrast of

resistivity variation is shown around the border between this low resistivity distribution and

high resistivity distribution at the northern part and its contour lines are straight in WNW-ESE

direction and indicate the resistivity discontinuity.


S-40

April 2015



Tendaho-2 (Ayrobera) site Boseti site


Figure 6.1 The panel diagrams of the resistivity plan maps created from MT/TEM survey results

6.5 Interpretation of Resistivity Structure in Geothermal Sites

6.5.1 Tendaho-2 (Ayrobera) Site

Figure 6.2 shows the resistivity distribution maps at different elevations, EL+200 m, EL+0 m, EL-700

m, EL-1,500 m, and EL-2,500 m. In this diagram, low resistivity zones (less than 10 ohm-m) are

remarkably dominant at EL 200 m and EL 0 m level; a low resistivity zone extending NW-SE

direction becomes apparent at El.-700 m level and downward though the distinctiveness tends to fade

out downward. The zone of NW-SE direction that is well in accordance to the general trend of the

Tendaho Graben, is considered to be an intensely fractured zone, delineated higher resistive zones

(intact rock zones) on both side of the west and the east. The fractured zone could be a reservoir

because high permeability would be expected.

For interpreting the cross sectional model, existing information are available here in Tendaho. In

Tendaho-1 (Dubti), about 13 km south-east from the site, six (6) test wells were drilled from 1994 to

1998. Among those, TD-1 and TD-2 are useful to refer. The relevant information of the two wells


S-41 April 2015



were summarized in Table 6.3. According to the table, the depth of the measured resistivity 5 ohm-m

ranges from 530 m to 580 m; whereas the depth of the measured temperature 245 – 250 oC ranges

from 450 m to 600 m. From this well corresponding relation between the depths of the resistivity and

the temperature, the depth of 5 ohm-m may be considered as the bottom of the cap layer or the top of

the reservoir in Tendaho area.

Table 6.3 Existing Test Well Data in Tendaho-1 (Dubti)

Name of Zone

TD-1 TD-2

Resistivity (Measured

depth)

Temperature (Measured

depth)

Alteration, Inferred Temp.

(Measured depth)

Resistivity (Measured

depth)

Temperature (Measured

depth)

Alteration, Inferred Temp.

(Measured depth)

1) Resistive over burden

Resistive <150 ºC Non-alteration

50-100 ºC , (95 m)

Resistive <150 ºC Non-alteration ,

50-100 ºC, (50 m)

2) Low resistive zone

<5 ohm-m, (580 m)

150 - 250 ºC, (600 m)

Argillized , 100-250 ºC,

(350 m)

<5 ohm-m (530 m)

150 º- 245 ºC

(450 m)


(280 m) 3) High

resistive zone

>5 ohm-m

250 ºC Chlorite- Epidote,

250-300 ºC

>5 ohm-m

245 ºC Chlorite- Epidote,

250-300 ºC

Source: Aquator (1994) and Aquator (1995), Compiled by JICA Project Team

Figure 6.3 shows NE-SW cross section of the resistivity. In the Figure 6.3, it is apparent that a zone

of low resistivity goes down at the middle part of the analysis section. This low resistivity zone was

interpreted as a fault fracture zones that runs NW-SE direction, and the fault zone may be the

reservoir. From the Figure 6.2, it is apparent that the reservoir is capped by a low resistivity layer,

and delineated by high resistivity zones on both sides. As the layer with resistivity lower that 5

ohm-m was interpreted as cap layer (“Cap rock”), the bottom depth of the cap layer is estimated to

range from 300 m to 1,200 m on the top of the inferred reservoir. Table 6.4 summarized the

interpretation of the reservoir structure.

Table 6.4 Interpretation of MT/TEM Survey Results with Alteration Mineral Occurrence and

Temperature in Tendaho-2 (Ayrobera)

Zone Interpretation of Reservoir

Resistivity Depth (GL-m) Interpretation of Temperature 1) Resistive

overburden >10 ohm-m Less than 100 m 50-100 oC

2) Low resistivity zone

Less than 5 ohm-m

Approximately 100–500 m

100-250 oC

3) High resistive zone

>5 ohm-m (40–60 ohm-m)

Deeper than 300– 1,200 m

250-300 oC



S-42

April 2015




Figure 6.2 Schematic Panel Diagram of Resistivity Distribution and Interpretation in

Tendaho-2 (Ayrobera)

Basaltic Volcanic rocks and Alluvial Sediments with salt accumulation on ground

Argillized Zone (less than 5ohm-m, more than 100 oC)

Argillized

Chl-Ep

ArgillizedChl-Ep

Chl-Ep

Chl-Ep

Transition Zone between Argillized to Chrolite-Epidote Zone (boundary: 5ohm-m, Approx 250 oC)

Chl-Ep Zone(Reservoir: between 40-60 ohm-m, More than 250 oC)

Fa-2Fa-1(Surface Elevation 375m)

(GL-175m)

(GL-375m)

(GL-1075m)

(GL-1875m)

(GL-2875m)



S-43 April 2015




Figure 6.3 Schematic Section of Tendaho-2 (Ayrobera)

6.5.2 Boseti Geothermal Site

Figure 6.4 shows the resistivity distribution maps at different elevations, EL+1,250 m, EL+1,200 m,

EL+50m, EL+0 m, EL-500 m and EL-1,000 m. In this diagram, resistivity higher than 100 ohm-m

observed at surface level is interpreted as a new lava layer. The lower resistivity zones less than 5

ohm-m are remarkably dominant at EL 500 m level: a low resistivity zone extending N-S direction

becomes apparent at EL 0 m level and downward though the distinctiveness tends to fade out

downwards. The zone is well in accordance to the faults extending to NNE-SSW direction. The low

resistivity zone therefore may be interpreted as a fault zone delineated on the both sides by resistive

zones.

Figure 6.5 shows the WNW-ESE cross section of the resistivity. In Figure 6.5, it is apparent that a

wide zone (channel) of lower resistivity goes down. The low resistivity zone was interpreted in this

figure as a fault zone running NNE-SSW direction. It is apparent that the reservoir is capped by a

low resistivity layer, and delineated by higher resistivity zones on both side. Therefore, the low

resistivity zone could be interpreted as a geothermal reservoir. It was interpreted in Tendaho that the

layer of resistivity lower that 5 ohm-m would be a cap layer (cap rock), the bottom depth of the cap

layer is estimated to range from GL-800 m to GL-900 m as shown in Figure 6.5. Table 6.5

summarized the interpretation of the inferred reservoir.

250 oC

FumaroleArea

Fa-2Fa-1

Argillized

Chl-Ep

SW NE


S-44 April 2015



Table 6.5 Interpretation of MT/TEM Survey Results with Alteration Mineral Occurrence and

Temperature in Boseti

Zone Interpretation of Reservoir Resistivity Depth (GL-m) Interpretation of Temperature

1) Resistive overburden

10–150 ohm-m Less than 300–500 m 50-100 oC


Less than 5 ohm-m

Approximately 500–900 m

100-250 oC


>5 ohm-m (25–40 ohm-m)

Deeper than 800– 900 m

250-300 oC



S-45

April 2015




Figure 6.4 Schematic Panel Diagram of Resistivity Distribution and Interpretation in Boseti

(Surface Elevation 1300m)

(GL-100m)

(GL-800m)

(GL-1300m)

(GL-1800m)

(GL-2300m)

Lava and Volcanic Depositswith hydrothermal alteration

Top of Argillized Zone (under 5 ohm-m, approx. 100 oC)

Middle of ArgillizedZone

Transition Zone between Argillized to Chrolite-Epidote Zone (boundary: 5 ohm-m, Approx 250 oC)

Chl-Ep Alteration Zone (as Reservoir: between 25-40 ohm-m)


Chl-Ep Chl-Ep

Chl-Ep

Argillized

Chl-Ep Chl-Ep

Fb-2Fb-1

Argillized

Argillized


S-46 April 2015




Figure 6.5 Schematic Section of Boseti Geothermal Site

Argillized

Chl-Ep

100 oC

250 oC

WNW ESE

Fb-2Fb-1


S-47 April 2015



7. PROPOSAL FOR PRELIMINARY GEOTHERMAL RESERVOIR MODEL AND TARGET FOR GEOTHERMAL

TEST WELLS

7.1 Purpose

Based on the geological, geochemical and geophysical survey conducted, preliminary reservoir

model was proposed. Targets of test wells was also proposed on the basis of the proposed reservoir

models

7.2 Purpose

Based on the geological, geochemical and geophysical survey conducted, preliminary reservoir

model will be proposed in this chapter. Targets of test wells will also proposed on the basis of the

proposed reservoir models

7.3 Tendaho-2 (Ayrobera) Geothermal Site

7.2.1 Interpretation of Survey Results

Table 7.1 shows the summary and interpretation of survey results and features as topographic

features, result of geological and geochemical surveys and MT/TEM survey that is necessary for

preparing preliminary geothermal structural model in Tendaho-2 (Ayrobera) site.

Table 7.1 Summary and Interpretation of survey results and features for Geothermal

Structural Modelling

Items Features Geology Papers

Satellite Imagery Field Survey

Located at Manda-Harraro Graben. Mainly composed of basaltic lavas and pyroclastics, and sediments of Afar

Stratoid (Pliocene-Pleistocene). Recent basalt lava (Pleistocene) by fissure eruption is observed at the southwest of the survey area.

Those volcanic rocks are covered by alluvial deposit in Ayrobera. Test Well Six test wells were drilled at Tendaho-3 (Dubti) located at 9-12km south of

the site. Altered clay minerals (GL-50 to 350m), chlorite – epidote (below

GL-350m) are observed at some test wells, interpreted as cap rock and geothermal reservoir.

Test well Flow rate Temp. Depth (GL-)

TD-2 13kg/s, 46.8t/h 220℃ 890m TD-4 70kg/s, 252t/h 216℃ 250m TD-1 Very low 270℃ 880-900m

1,190-1,265m Thick sedimentary rock intercalated with basaltic rock was observed at the

depth of approx. 2,000m at TD-4 test well (located at 9km southwest of the site)

Basaltic rocks are observed below 2,000m at TD-4. Fault/ Fracture System

Papers Satellite Imagery Field Survey

The Graben is under tensile stress and NW-SE normal fault and fracture system is developed.

Spreading axis is located at the southwest of the site, and steep normal faults, dipping to the southwest, are well developed.


S-48

April 2015



Items Features Geophysical

Survey NW-SE low resistivity zone are found at the depth of GL-700m to

GL-2,500m in the center of the survey area by MT/TEM survey. According to the result of gravity survey, the above-mentioned zone is the

boundary between high-gravity area (northeast) and low-gravity area (southwest).

According to the result of magnetic survey, the above-mentioned zone is the boundary between high-magnetic intensity area (northeast) and low-magnetic intensity area (southwest). (Yohannes L.,2007)

TD-4 is located at southwest area, therefore the combination of low-gravity and low-magnetic intensity was resulted by thick sedimentary rock.

NW-SE low resistivity zone obtained by MT/TEM Survey is consistent with the boundary of other geophysical survey results, interpreted as fault zone.

Heat Source Geophysical Survey

Resistivity value is lower at the depth below 4,000m, may indicates heated zone caused by intrusion of basaltic magma.

Geothermal Fluid

Topography Satellite Imagery

Discharge is expected by Awash River and marsh zone, located at the north of the site.

Geochemical Analysis

Fumaroles of 99.3ºC were observed at the southwestern part. Result of geochemical analysis indicates 240-290ºC of geothermal fluid

temperature (by silica thermometer) Test Well Self flow of 1.8t/h (13kg/s), 220 ºC was confirmed at TD-2 Test well in

Tendaho-3 (Dubti). (DAmore et al., 1997) Cap Rock Structure

Geophysical Survey

A low resistivity zone (less than 5ohm-m) were found at the depth of GL-100m to GL-500m), may compose cap rock structure.

Test Well Altered clay minerals and zeolites are found at the depth of GL-50m to 350m in existing test wells in Tendaho-3 (Dubti).

The depth for occurrence of those minerals may be corresponded with the low resistivity zone (less than 5ohm-m).


7.2 Preliminary Geothermal Reservoir Model

The Conceptual Geothermal Reservoir Model in Ayrobera, which is indicated by the above features,

is prepared. The characteristics of the model is shown in Table 7.2, diagram and section are shown in

Figure 7.1 and Figure 7.2.

Table 7.2 Characteristics of Geothermal Reservoir Item Description

Geothermal Reservoir

Geothermal reservoir may be porous basalts and sandstones. North-eastern margin of the reservoir would be clear with normal faults in basaltic rock, where south-western margin would be along many sand layers in sedimentary rocks. Altered basaltic rocks, fine sandstones and siltstones would be distributed at the top of the reservoir as cap rock.

Geothermal Fluid Geothermal fluid may be discharged by Awash River and the ground, convecting in the ground restricted by faults and fault zones. Up-flow zone would be formed along the fault zone in the center of the survey area.

Heat Source Basaltic magma is expected as a heat source in the area, which would be located at the depth of 5-6 km.



S-49

April 2015




Figure 7.1 Preliminary Geothermal Reservoir Model in Tendaho-2 (Ayrobera) Site


Figure 7.2 Preliminary Geothermal Reservoir Model (Section) in Tendaho-2 (Ayrobera) Site

Basaltic Rock

Spreading Axis

N

2km

2km2km

Basalt dykeSedimentsBasaltFaultSpreading Axis

FumaroleCap RockReservoirFluidGeothermal FluidHeat Source

Fumaroles

CAP ROCK

NESW

Basaltic Rock

Basaltic Rock

Alluvial Deposit

Heat Source(Basaltic magma)


Sedimentary Rocks

Basaltic RocksBasaltic Rocks


S-50 April 2015



7.2.3 Preliminary Target for Test Well Drilling

According to the geothermal model, a wide channel of NW-SE high temperature convective zone (low

resistivity zone) in the centre of the study area. It is expected that the drilling depth needs to be about

2,000 m to drill up to the assumed faults and high temperature convective zone. Tentative target and

specification of the test well drilling is summarized in Table 7.3 and Table 7.4. Selected drilling

locations are shown in Figure 7.3 and Figure 7.4.

Table 7.3 Tentative Target for Test Well Drilling in Tendaho-2 (Ayrobera)

Area Target Well Type AY-1 Area NW-SE subsurface normal fault zone (dipping to SW) Directional well AY-2 Area NW-SE subsurface normal fault zone (dipping to SW) Vertical Well AY-3 Area NW-SE Normal faults at Fumaroles Point (dipping to SW) Vertical Well


Table 7.4 Tentative Specification of Test Well Drilling in Tendaho-2 (Ayrobera)

Item AY 1 AY 2 AY 3

Outline of the target Aiming at NW-SE low resistivity zone (Fault zone) at the centre.

Aiming at NW-SE low resistivity zone (Fault zone) at northern part.

Aiming at NW-SE Fault zone at Fumaroles point.

Location of the target from well head

Direction from True North standard : N 57°E, Vertical depth: 1,840 m Horizontal distance: 600 m

Vertical depth: 2,000 m

Vertical depth: 2,000 m

Approximate depth of the target (GL-m)

1,000–1,840 1,500-2,000 1,500–2,000

Estimated temperature at the target

Approx. 250–300 oC Approx. 250–300 oC Approx. 250–300 oC

KOP 800 m - -

Drilling depth to bottom

1,840 m 2,000 m 2,000 m

KOP :Kick-Off Point Source: JICA Project Team


S-51

April 2015




Figure 7.3 Test Well Drilling Plan in Ayrobera (Tendaho-2)


Figure 7.4 Schematic Section of Test Well Drilling in Ayrobera (Tendaho-2)

NESW

AY-1 AY-2AY-3

EL-1500m(GL-1800m)

GeothermalReservoir

CAP ROCK


Sedimentary Rocks

Basaltic RocksBasaltic Rocks


S-52 April 2015



7.3 Boseti Geothermal Site

7.3.1 Interpretation of Survey Results

Table 7.5 shows the summary and interpretation of survey results and features as topographic

features, result of geological and geochemical surveys and MT/TEM survey that is necessary for

preparing preliminary geothermal structural model in Boseti site.

Table 7.5 Summary and Interpretation of survey results and features for Geothermal

Structural Modelling

Item Features Geology Geology Composed of basaltic-rhyolitic lava and pyroclastic rocks, and

sedimentary rocks (conglomerate-sandstone) of Nazreth Group (Pliocene-Pleistocene).

Boseti volcano and erupted lavas (obsidians), basalt lava at the surface in the northern part are classified as Wonji Group (Pleistocene), underlain by Nazreth group with unconformity.

Fault/Fracture System

Satellite Imagery Geology

Many normal faults are developed at the direction of NNE-SSW, which is concordant with the direction of Rift Valley.

Geophysical Survey

Low resistivity zone is observed at the depth of GL-800m to GL-2,300m in the center of survey area and its direction is concordant with normal faults on the ground.

Heat Source Geology According to the result of topographic analysis, lavas were intruded and erupted along the NNE-SSW fault (Fb-2) in the center of survey area (Korme et.al., 1997).

Gravity Survey

High-density rock is assumed at the depth of GL-2,000m below Boseti Volcano (D.G. Cornwell et al., 2006).

Geothermal Fluid Geochemical Analysis

Fumaroles are observed along NNE-SSW fault (Fb-1) in the survey area.

Temperature of geothermal fluid would be 170-220°C, classified as Class C (by Silica Thermometer)

Cap Rock Structure Geophysical Survey

Low resistivity zone (less than 5ohm-m) which was found at the depth of GL-800m to GL-900m is interpreted as cap rock.

Source: JICA Project team

7.3.2 Preliminary Geothermal Reservoir Model

The Conceptual Geothermal Reservoir Model in Boseti, which is indicated by the above features, is

prepared. The characteristics of the model is shown in Table 7.6, diagram and section are shown in

Figure 7.5 and Figure 7.6.

Table 7.6 Characteristics of Geothermal Reservoir Item Description


Basalt-rhyolite lava and pyroclastic rocks, and sedimentary rocks along the NNE-SSW normal faults are expected as a geothermal reservoir in the area. The margin would be clearly divided by steep faults and/or fractures. Cap rock is assumed at the top of reservoir, which is mainly composed of clay layers altered from basaltic-rhyolitic rocks.

Geothermal Fluid Fluid may be discharged by the surface and aquifers in Nazreth Group. Geothermal fluid is convecting in the ground restricted by faults and fault zones. Up-flow zone would be formed along the fault zone in the center of the survey area.

Heat Source Intrusive rock(s) which may be distributed along NNE-SSW at the depth below 2,000m.

Source: JICA Project team


S-53

April 2015




Figure 7.5 Preliminary Geothermal Reservoir Model in Boseti site


Figure 7.6 Preliminary Geothermal Reservoir Model (Section) in Boseti site

？？

ESEWNW

Volcanic Vent

Cap RockReservoirIntrusiveGeothermal Fluid

FumarolesFaultsFluidsVolcanic Vent

N1km

1km1km

Fb-1

Fb-2

？

Normal Fault

Boseti Volcanic Body

Normal Faults

Intrusive

CAP ROCK


Basaltic/ Rhyolitic Rocks Intrusive Rock

Basaltic/ Rhyolitic Rocks

FumaroleFb-1 Fb-2


S-54 April 2015



7.3.3 Preliminary Target for Test Well Drilling

According to the geothermal model, a wide channel of NNE-SSW high temperature convective zone

(low resistivity zone) associated with two distinctive faults are observed on the ground, namely Fb-1

and Fb-2. This high-temperature zone may continue toward the south, below Boseti Volcano, and it

seems that the reservoir temperature may increase as the zone gets closer to the volcano. It is expected

that the drilling depth needs to be about 2,000 m to drill up to the assumed high temperature

convective zone with subsurface fault zones. Tentative target and specification of the test well is

proposed in Table 7.7 and Table 7.8. Selected drilling locations are shown in Figure 7.7 and Figure

7.8.

Table 7.7 Tentative Specification of Test Well Drilling in Boseti Target Area Target Test Drilling

BS-1 Area NNE-SSW low resistivity zone along Fault Fb-1 where many fumaroles are located.

Directive Well

BS-2 Area Center of the reservoir (low resistivity zone) along Fault Fb-2 near the volcanic body.

Directive Well

BS-3 Area Center of the reservoir (low resistivity zone) along Fault Fb-2 where the Fault is clearly observed on the ground.

Directive Well


Table 7.8 Tentative Specification of Test Well Drilling in Boseti

Item BS-1 BS-2 BS-3 Outline of the target

Aiming at NNE-SSW low resistivity zone along Fault Fb-1.



Location of the target from wellhead

Direction from true North standard : S 30°E, Vertical depth: 1,840 m Horizontal distance: 600 m

Direction from true North standard : S30°E, Vertical depth: 1,840 m Horizontal distance: 600 m

Direction from true North standard : S30°E, Vertical depth: 1,840 m Horizontal distance: 600 m

Approximate depth of the target (GL-m)

1,000–1,840 1,000–1,840 1,000–1,840

Estimated temperature at the target

Approx. 250–300 oC Approx. 250–300 oC Approx. 250–300 oC

KOP (kick off point)

800 m 800 m 800 m

Drilling depth to bottom

1,840 m 1,840 m 1,840 m



S-55

April 2015




Figure 7.7 Test Well Drilling Plan in Boseti


Figure 7.8 Schematic Section of Test Well Drilling in Boseti

GeothermalReservoir

？？

ESEWNW

？

CAP ROCK



Intrusive Rock


FumaroleFb-1 Fb-2


S-56 April 2015



8. DATABASE CONSTRUCTION

8.1 Objective and Utilization of the Database A geothermal database was constructed to systematically store various geothermal data such as

geological, geochemical, and geophysical test results as well as information on topography and

infrastructures. “G*BASE” has been produced by Geothermal Energy Research and Development

(GERD) Co. Ltd., Japan based on Oracle7/8TM exclusively for geothermal-related database.

8.2 Structure of the Database The database was constructed using the G*BASE software by digitizing all information for each

prospect. The data and information that may be input in G*BASE are summarized in Table 8.1.

Table 8.1 Database Structure of “G*BASE” Data Type Information Examples

Depth (Z, numerical data)

Well logging, lost circulation/feed point. casing program, well direction coordinates, geologic column

2D Discrete data (X, Y, numerical)

Altitude, depth to the top of rock phases, planar distributions of geophysical and geochemical survey

3D Discrete data (X, Y, X; numerical)

Geophysical survey (MT resistivity, vertical electronic sounding, etc.), reservoir simulation results

Chronological data (t; numerical)

Well test, production-reinjection well record, pressure-temp monitoring, geochemistry monitoring, etc.

Mark data Place name, manifestation point (hot spring, fumaroles), sampling point coordination, volcano

Polygon data Road, river, lake, facilities, boundary line, geological maps, faults, caldera

Image data (planar or sectional pictorial image)

Satellite imagery, geological maps, geological cross sections, seismic reflection survey, planar section at depths

Geochemical data Geochemical analysis results


Instructions and training were given to the GSE staff through training in Japan and on-the-job

training in Ethiopia so that GSE is able to update the database in Ethiopia. A detailed operations

manual for G*BASE is provided to GSE in a separate volume.

8.3 Data and Information in G*BASE The JICA Project Team constructed the database and input geothermal data provided by GSE and

acquired in this study. Table 8.2 presents the list of input data and information.


S-57

April 2015



Table 8.2 Geothermal Data in G*BASE Classification Input Data

Basic Information Topographic Contour River Lake Primary Roads Railway

Geological Data Geological Map Fault Volcano Caldera

Topography (Remote Sensing Data)

Hydrothermal Alternation Circular Landform Lineament

Surface Survey Geothermal Manifestation Sampling Location

Geochemical Geochemical Analysis Result Geophysical MT/TEM Survey Map

VES Map Magnetic Sounding Map Bouguer Anomaly Map Microseismic Map

Drilling Well Data Well Location Well Curve Casing Program Geological Column Well Event (Lost circulation point)

Well Logging Data Temperature Logging Pressure Logging Well Head Pressure Test Injection Test Fall-off Test Production Test Discharge Flow Test Inference Test Build-up Test


The JICA Project Team had imported into the database not only the survey results of this study but

also data collected from GSE. Using one of the applications in G*BASE, the 2-D and 3-D model

may be built that enables to construct geothermal reservoir models and to conduct fluid simulation.

8.4 Management and Upgrading of the Database It is necessary that GSE upgrade and manage the database properly when it obtains new geothermal

data. Before commencement of this study, existing geothermal data had not been utilized fully by the

GSE staff because most of the data were scattered and not accumulated properly. Moreover, there

were some missing data (including logging data, acquisition date, test conditions, and data unit, etc.).

To avoid the same mistakes, GSE is expected to accumulate all data into the G*BASE database

properly. In utilizing the database, GSE should plan further geothermal surveys and drilling

programs and simulate several tests of geothermal reservoirs and fluids.


S-58

April 2015



9. PROPOSED SURVEY UP TO TEST WELL DRILLING

We made recommendations on further surface surveys and an approach to creating the new

implementation organization EEGeD.

9.1 Recommendations on Surface Surveys in the Selected Sites

9.1.1 Target sites to be additionally surveyed

In addition to Tendaho-2 (Ayrobera) and Boseti, we proposed to include Butajira in the survey

program as a portfolio approach. Butajira was recognized as a seemingly promising site that was

accidentally identified in May 2014.

9.1.2 Approach of the additional survey

We recommend adopting a two step approach, namely, the first step for additional surface survey in the

nominated three sites, and the second step for temperature gradient well drillings as shown in Table

9.1.

Table 9.1 Proposed Additional Surface Survey and TG Wells

Capacity Building Equipment

Micro-seismicity ☑ - - -T/C,Survey equipment

Gravity Survey (Existing data) ☑ ☑ -T/C,Survey equipment

MagneticSurvey

(Existing data) ☑ ☑ Survey equipment T/C

MT/TEMSurvey ☑ - ☑ Survey equipment T/C

MT 3D Analysis ☑ - - - T/C

2m DepthTemperatureSurvey

☑ ☑ ☑ - T/C,Survey materials

Geological andGeochemicalsurvey

done done ☑- Geologist,- Geochemist

Lobo analysis T/C,Survey materials

Preliminry ESIA done done ☑ - -T/C,(out-sourcing)

2nd

TG wells

3rd Test Wells

At one or tow promising site/s

At the most promising site

- Geologists,- Geophysists,- Reservoir engineers

- Drilling service,- Drilling managers,- Geologists,- Reservoir engineers

GSE Input

Drilling machine,Supportingequipment, Drillingcrew

T/C,Drilling consumables

Step Survey Items Ayrobera Boseti

Butajira(if additionally

requested)

ESIA: Environmental, Social Impact Assessment

1st

JICA Assistance

Note: TG wells: Temperature gradient wells; T/C: Technical cooperation (Source：JICA Project Team)

two

Labo


S-59

April 2015



9.2 Proposal for on Master Plan Formulation Project on Establishment of EEGeD

9.2.1 Special Purpose Public Entity (Enterprise) The recommended new special purpose entity temporarily named as Ethiopian Enterprise for

Geothermal Energy Development (EEGeD). The mandates of EEGeD may be as follows:

To undertake the geothermal resource surface survey and test drilling,

To undertake project feasibility study when necessary for a future business of EEGeD,

To undertake field development wherever possible, and

To operate steam production and sales wherever possible.

There may be a possibility that EEGeD may extend its operation to power generation. The merits of

forming EEGeD are as follows:

EEGeD will be able to concentrate its efforts to geothermal development mainly for the purpose

of electricity generation;

EEGeD will also be able to accumulate its knowledge and experiences within the organization,

which will accelerate geothermal development; and

EEGeD, as the single focal point for geothermal development in Ethiopia, will be able to attract

donors’ attention, which will make financial arrangement much easier.

9.2.2 Characteristics of EEGeD The new geothermal-specialized public entity EEGeD shall be financially sustainable once it

becomes a fully-fledged operation. It is for this reason that EEGeD shall undertake steam production

and sales, thereby ensuring stable revenue.

9.2.3 Proposal for the Master Plan Formulation Project on Establishment of EEGeD To establish the new enterprise EEGeD, a design of institutional and regulations will be necessary.

Even though the final status of EEGeD shall be a financially sustainable organization, there will be a

transitional period when the EEGeD may need financial supports until its fully-fledged operation.

Thus, we would propose a Master Plan Formulation Project to be implemented. The proposed Terms

of Reference is shown in the Table

Table 9.2 Proposed TOR of a Master Plan Project on Establishment of EEGeD Rationale for EEGeD Vision and Mission Situation analysis

(Assessment of human, physical and financial resources) Business model

(Value chain mapping and ownership structure) Human Resource Development (Organization and staffing) Legal and regulatory framework Geothermal resource development Financial plan Steam Sales Agreement (SSA) Action Plan for Formation of EEGeD


S-60

April 2015



10. THE WAY FORWARD: CONCLUSIONS AND RECOMMENDATIONS

The Project Team assessed geothermal resources of the nominated 22 sites in Ethiopia based on

existing information, remote sensing analysis, field geological and geochemical survey followed by its

laboratory analysis, and environmental-social impact assessment. Thereby, the Team formulated the

Master Plan on Development of Geothermal Energy in Ethiopia.

Prior to describing conclusions and recommendations, we would first reconfirm and emphasize its

significances of the geothermal energy development in Ethiopia:

Geothermal power generation provides reliable electricity supply as base load throughout a

year;

Geothermal energy is supreme to other climate-dependent renewable energies such as wind,

solar and/or others;

Geothermal energy will reduce drought risks of hydropower-dependent Ethiopian power

supply;

Thus, priority has to be given to the earliest and the maximum development of geothermal

energy.

The conclusions and recommendations the Project Team reached are as follows.

10.1 Conclusions The geothermal resources of the target sites are estimated at a 4,200 MW as the most probable

occurrence probability (O/P), a 2,100 MW as 80% O/P, and a 10,800 MW as the 20% O/P. This

estimation is classified as “inferred geothermal resource” since only surface surveys were

conducted for the estimation. This estimation needs to be refined to a level of “indicated or

measured geothermal resources” through conducting geophysical survey and test well drilling

for formulating more specific development plans.

The environmental and social impact assessment identified no significant adverse impacts on

natural and social environment with a few exceptions that were eventually ranked at lower

priorities.

The 22 sites are classified into the five priority groups, i.e. Priority-S, A, B, C and D on the

basis of the multi-criteria analysis conducted. The analysis concluded that a 610 MW of the

Priority-S should be developed for the period of 2014 to 2018, an approximately 2,800 MW of

the Priority A and B for the period of 2019 to 2025, and an approximately 1,100 MW of the

Priority-C and D for the period of 2026 to 2037.

The analysis also concluded that the geothermal sites of the Priority A and B should first be

developed prior to some of the wind and solar power generating facilities planed by EEP. EEP

presently plans to install a total of an approximately 1,200 MW of wind and solar power


S-61

April 2015



facilities by 2018.

The financial analysis revealed that the generation cost could be below the present domestic

tariff level only when the Priority-A sites are developed with most concessional financing

programs such as Japan’s ODA loans; The generation cost could then be below the present

exporting tariff level when the Priority-A and B sites are developed with more concessional

financing programs such as World Bank loans; the generation cost will exceed the both tariff

levels if geothermal sites are developed with private funds. In other words, public financing

schemes shall be utilized for the geothermal development under the present tariff policy. If

private investments are to be promoted, financial and/or institutional supporting policies will

have to be established.

The geothermal development has to be implemented by a public entity who shall handle

projects with public financing schemes. A new public entity named EEGeD needs to be

established by merging the existing geothermal related sections in GSE and EEP. Financial

sustainability of EEGeD could be maintained by selling steam to the electricity producer (EEP,

etc). Private firms, however, should be allowed to participate in any stage of the geothermal

energy development.

The Project Team identified three priority sites, i.e. Tendaho-2 (Ayrobera) of Priority-A, and

Boseti and Meteka of Priority-B, from green fields where other donors or private firms have not

yet committed. Out of those three, geophysical survey was conducted in Tendaho-2 (Ayrobera)

and Boseti. Based on the geophysical survey conducted, the outer limits of geothermal reservoir

were preliminarily inferred for each site; thereby, targets of test wells were proposed.

10.2 Recommendations Geothermal power generation will be of paramount importance as stable base load energy for the

hydropower dependent Ethiopia power supply system, which is susceptible to climate change and

unstable in drought years. The Project Team proposes the following recommendations in order to

accelerate the geothermal development in Ethiopia.

To ensure the smooth implementation of the Priority-S projects that are already committed by

other donors or a private firm;

To implement, at an earliest convenient, an additional surface survey including temperature

gradient wells at Tendaho-2 (Ayrobera) and Boseti. In Butajira that was first identified in 2014,

surface survey including geophysical survey shall be conducted.

To realize, as earliest as possible after the above survey, test well drillings at Tendaho-2

(Ayrobera), Boseti or Butajira wherever deemed to be the most promising;

To conduct, as an urgent requirement, a master plan project for the establishment of EEGeD; to

implement capacity building to EEGeD, at very earliest convenient, in order to accelerate the

geothermal development; and

To review and update the geothermal resource assessment as further exploration proceeds,


S-62

April 2015



To review and update the Master Plan from time to time, since the Ethiopia economy is being

rapidly growing and the world economic circumstances are drastically changing.


S-63

April 2015

The project for Formulating Master Plan on Development of Geothermal Energy in Ethiopia Final Report

THE PROJECT FOR FORMULATING MASTER PLAN ON DEVELOPMENT OF GEOTHERMAL ENERGY IN ETHIOPIA

FINAL REPORT

APRIL 2015

Location Map

Executive Summary

Contents

Abbreviations

page CHAPTER 1 BACKGROUND OF THE PROJECT ................................................................... 1-1 1.1 Background ............................................................................................................................ 1-1 1.2 Objectives and Scope of Work of the Project ...................................................................... 1-2

1.2.1 Objectives................................................................................................................. 1-2

1.2.2 Counterpart and Relevant Organizations ................................................................. 1-2

1.2.3 Target Sites ............................................................................................................... 1-3

1.2.4 Member and Schedule of Project ............................................................................. 1-4

CHAPTER 2 ELECTRICITY DEVELOPMENT PLAN .......................................................... 2-1 2.1 Growth and Transformation Plan ........................................................................................ 2-1

2.1.1 Overview .................................................................................................................. 2-1

2.1.2 Energy Sector Plan ................................................................................................... 2-2

2.2 Overview of Power Sector ..................................................................................................... 2-3 2.2.1 Policy, Laws, Regulations, and Strategy .................................................................. 2-3

2.2.2 Power Sector Institutions ......................................................................................... 2-4

2.2.3 Power Demand Forecast .......................................................................................... 2-8

2.2.4 Power Generation Planning.................................................................................... 2-14

2.2.5 Transmission Planning ........................................................................................... 2-21

2.2.6 Financing and Tariff ............................................................................................... 2-25

2.3 Geothermal Power Development........................................................................................ 2-26 2.3.1 Existing Geothermal Development Plans .............................................................. 2-26

2.3.2 Committed Geothermal Power Development Plans............................................... 2-28

2.3.3 Target of the Geothermal Power Development ...................................................... 2-29

2.3.4 Superiority of Geothermal Power Generation ........................................................ 2-30

CHAPTER 3 GEOTHERMAL POTENTIAL SURVEY ........................................................... 3-1 3.1 Geology ................................................................................................................................... 3-1

Nippon Koei Co., Ltd. i April 2015 JMC Geothermal Engineering Co., Ltd. Sumiko Resources Exploration & Development Co., Ltd.


3.1.1 Tectonics .................................................................................................................. 3-1

3.1.2 Regional Geological Setting .................................................................................... 3-1

3.1.3 Regional Geological Structure ................................................................................. 3-2

3.2 Collection of Existing Information ....................................................................................... 3-3 3.2.1 Objective .................................................................................................................. 3-3

3.2.2 Regional Reports ...................................................................................................... 3-3

3.2.3 Detailed Geothermal Survey .................................................................................... 3-4

3.2.4 Feasibility Study ...................................................................................................... 3-4

3.2.5 Geothermal Plant Construction /Operation and Maintenance .................................. 3-5

3.3 Satellite Data Analysis ........................................................................................................... 3-5 3.3.1 Objectives................................................................................................................. 3-5

3.3.2 Methodology ............................................................................................................ 3-5

3.3.3 Results ...................................................................................................................... 3-6

3.4 Results of the Field Survey and Laboratory Analysis ........................................................ 3-8 3.4.1 Geological Survey .................................................................................................... 3-8

3.4.2 Geochemistry ......................................................................................................... 3-15

3.5 Preliminary Reservoir Assessment ..................................................................................... 3-34 3.5.1 Objectives............................................................................................................... 3-34

3.5.2 Definition of Resource and Reserve ...................................................................... 3-34

3.5.3 Methodology of Reservoir Resource Assessment – Volumetric Method ............... 3-36

3.5.4 Probabilistic Approach － Monte-Carlo Method ................................................. 3-38

3.5.5 Proposed the parameters ........................................................................................ 3-38

3.5.6 Proposal of the reservoir volumes .......................................................................... 3-38

3.5.7 Determination of Reservoir thickness .................................................................... 3-39

3.5.8 Determination of Average Reservoir Temperatures ............................................... 3-40

3.5.9 Geothermal Power Plant Type Assumed ................................................................ 3-40

3.5.10 Results of reservoir assessment .............................................................................. 3-40

(References) .......................................................................................................................... 3-44

CHAPTER 4 ENVIRONMENTAL AND SOCIAL CONSIDERATIONS ............................... 4-1 4.1 Outline of Environmental and Social Impact Assessment Study ...................................... 4-1

4.1.1 Tasks of ESIA Study ................................................................................................ 4-1

4.1.2 Objectives of ESIA Study ........................................................................................ 4-1

4.1.3 Area Covered in the ESIA Study ............................................................................. 4-2

4.2 Environmental Laws and Regulations ................................................................................. 4-2 4.2.1 Framework of environmental and social laws and regulations ................................ 4-2

4.2.2 Institutional Framework of Environmental Management in FDRE ....................... 4-10

4.3 Baseline Survey .................................................................................................................... 4-11 4.3.1 Methodology of Baseline survey ........................................................................... 4-11

Nippon Koei Co., Ltd. ii April 2015 JMC Geothermal Engineering Co., Ltd. Sumiko Resources Exploration & Development Co., Ltd.


4.3.2 Outline of the Baseline data ................................................................................... 4-12

4.4 Strategic Environmental Assessment (SEA) ..................................................................... 4-15 4.4.1 Ethiopian energy policy on geothermal development ............................................ 4-15

4.4.2 Energy Resource Alternatives ................................................................................ 4-16

4.4.3 Project Alternatives ................................................................................................ 4-17

4.5 Implementation of IEE ........................................................................................................ 4-18 4.5.1 Project Categorization ............................................................................................ 4-19

4.5.2 Scoping for Initial Environmental Examination .................................................... 4-20

4.5.3 Socio-environmental Interactions .......................................................................... 4-23

4.5.4 Utilization of Water ................................................................................................ 4-24

4.5.5 Displacement and Resettlement ............................................................................. 4-25

4.6 Environmental Management Plan ..................................................................................... 4-28 4.6.1 Environmental Management Plan (EMP) .............................................................. 4-28

4.6.2 Monitoring plan ...................................................................................................... 4-29

4.7 Consultation with stakeholder ............................................................................................ 4-30 4.8 Conclusion and Recommendation ...................................................................................... 4-31

4.8.1 Conclusion ............................................................................................................. 4-31

4.8.2 Recommendation ................................................................................................... 4-32

CHAPTER 5 FORMULATION OF MASTER PLAN ............................................................... 5-1 5.1 Target and Methodology ....................................................................................................... 5-1

5.1.1 Target of the Master Plan ......................................................................................... 5-1

5.1.2 Methodology of the Master Plan .............................................................................. 5-1

5.2 Multi-Criteria Analysis for Prioritizing the Geological Prospects .................................... 5-2 5.2.1 Factors to be Considered .......................................................................................... 5-2

5.2.2 Prioritization of the Geothermal Prospects ............................................................ 5-13

5.3 Implementation Plan ........................................................................................................... 5-16 5.3.1 General Consideration ............................................................................................ 5-16

5.3.2 Development Plan .................................................................................................. 5-16

5.4 Financial Considerations for Geothermal Development .................................................. 5-20 5.5 Implementation Structure .................................................................................................. 5-22

5.5.1 Consideration of Structural Body for Geothermal Energy Development .............. 5-22

5.5.2 Special Purpose Public Entity (Enterprise) ............................................................ 5-25

5.6 On Direct Use of Geothermal Resources ........................................................................... 5-27 5.6.1 Present Status of Geothermal Resource ................................................................. 5-27

5.6.2 Proposals for Direct Uses of Geothermal Resources in Ethiopia ........................... 5-29

5.7 [REFERENCE] Models of Geothermal Power Development in International Practice ................................................................................................................................. 5-31 5.7.1 International Practice ............................................................................................. 5-31

Nippon Koei Co., Ltd. iii April 2015 JMC Geothermal Engineering Co., Ltd. Sumiko Resources Exploration & Development Co., Ltd.


5.7.2 Example of Kenya .................................................................................................. 5-31

5.7.3 Example of Geothermal Development in the Philippines ...................................... 5-32

5.7.4 Example – Indonesia .............................................................................................. 5-34

CHAPTER 6 GEOPHYSICAL SURVEY ................................................................................... 6-1 6.1 Objectives ............................................................................................................................... 6-1 6.2 Selection of the Target Sites .................................................................................................. 6-1 6.3 Selection of the Target Sites .................................................................................................. 6-1 6.4 Survey Results ........................................................................................................................ 6-2

6.4.1 Tendaho 2 (Ayrobera) Geothermal Field .................................................................. 6-2

6.4.2 Boseti Geothermal Field .......................................................................................... 6-4

6.4.3 Notes for Reservoir Modelling................................................................................. 6-6

6.5 Interpretation of Resistivity Structure in Geothermal Sites ............................................ 6-12 6.5.1 Tendaho 2 (Ayrobera) Site ..................................................................................... 6-12

6.5.2 Boseti Geothermal Site .......................................................................................... 6-16

CHAPTER 7 PROPOSAL FOR PRELIMINARY GEOTHERMAL RESERVOIR MODEL AND TARGET FOR GEOTHERMAL TEST WELLS ...................... 7-1

7.1 Purpose ................................................................................................................................... 7-1 7.2 Tendaho-2 (Ayrobera) Geothermal Site............................................................................... 7-1

7.2.1 Interpretation of Survey Results............................................................................... 7-1

7.2.2 Preliminary Geothermal Reservoir Model ............................................................... 7-2

7.2.3 Preliminary Target for Test Well Drilling ................................................................. 7-4

7.3 Boseti Geothermal Site .......................................................................................................... 7-6 7.3.1 Interpretation of Survey Results............................................................................... 7-6

7.3.2 Preliminary Geothermal Reservoir Model ............................................................... 7-6

7.3.3 Preliminary Target for Test Well Drilling ................................................................. 7-8

7.4 Recalculation of Geothermal Resources and Priority of Geothermal Development ........................................................................................................................ 7-10 7.4.1 Re-evaluation of Geothermal Potential .................................................................. 7-10

7.4.2 Review of Priority of Geothermal Development ................................................... 7-10

7.5 Drilling Plan ......................................................................................................................... 7-10 7.5.1 Test Drillings .......................................................................................................... 7-10

7.5.2 Considerations for Test Drilling ............................................................................. 7-12

CHAPTER 8 DATABASE CONSTRUCTION ........................................................................... 8-1 8.1 Objective and Utilization of the Database ........................................................................... 8-1 8.2 Structure of the Database ..................................................................................................... 8-1 8.3 Data and Information in G*BASE ....................................................................................... 8-3

Nippon Koei Co., Ltd. iv April 2015 JMC Geothermal Engineering Co., Ltd. Sumiko Resources Exploration & Development Co., Ltd.


8.4 Management and Upgrading of the Database..................................................................... 8-4

CHAPTER 9 PROPOSED SURVEY UP TO TEST WELL DRILLING ................................. 9-1 9.1 Recommendations on Surface Surveys in the Selected Sites ............................................. 9-1

9.1.1 Target sites to be additionally surveyed ................................................................... 9-1

9.1.2 Present development status of Butajira .................................................................... 9-1

9.1.3 Approach of the additional survey ........................................................................... 9-2

9.2 Proposal for on Master Plan Formulation Project on Establishment of EEGeD .................................................................................................................................... 9-3 9.2.1 Special Purpose Public Entity (Enterprise) .............................................................. 9-3

9.2.2 Characteristics of EEGeD ........................................................................................ 9-3

9.2.3 Proposal for the Master Plan Formulation Project on Establishment of

EEGeD ..................................................................................................................... 9-3

CHAPTER 10 THE WAY FORWARD: CONCLUSIONS AND RECOMMENDATIONS ..................................................................................... 10-1

Appendices Appendix-1: Remote Sensing Analysis

Appendix-2: Site Reconnaissance

Appendix-3: Volumetric Calculation Method

Appendix-4: Environmental and Social Impact Assessment

Appendix-5: Calculation of EIRR

Appendix-6: Geophysical Survey

Appendix-7: Database

Appendix-8: Minutes of Meeting

Appendix-9: Record photographs

Separate Volume: G*Base Operation Manual

Exchange Rate (as of April 2015)

1 USD = 116.94 JPY 1 ETB = 5.929 JPY

Nippon Koei Co., Ltd. v April 2015 JMC Geothermal Engineering Co., Ltd. Sumiko Resources Exploration & Development Co., Ltd.


Figures and Tables Figures

Figure 2.2.1 Organizational Chart of Power Sector in Ethiopia ................................................. 2-5

Figure 2.2.2 GSE Organization Chart ........................................................................................ 2-6

Figure 2.2.3 Organization Chart of Geothermal Section ............................................................ 2-6

Figure 2.2.4 EEP and EEU Organization Chart ......................................................................... 2-8

Figure 2.2.5 Electrical Sales and Number of Customers ........................................................... 2-9

Figure 2.2.6 Electrical Sales Growth by Category and Share in 2011 (GWh) ........................... 2-9

Figure 2.2.7 Energy Requirement Forecast including Exports (2012-2037) ........................... 2-13

Figure 2.2.8 Peak Demand Forecast including Exports (2012-2037) ...................................... 2-13

Figure 2.2.9 Location Map of Existing, Committed, and Proposed Hydropower Plants ......... 2-17

Figure 2.2.10 Existing and Committed Electrical Grid in Ethiopia ......................................... 2-22

Figure 2.2.11 Expansion Network Plan (left: short-term, right: long-term) ............................. 2-24

Figure 2.3.1 Installed Capacity and Reserve Margin ............................................................... 2-27

Figure 2.3.2 Energy Generation by Plant Type ........................................................................ 2-28

Figure 2.3.3 Targeted Installed Capacity of Geothermal Power Plant ..................................... 2-30

Figure 2.3.4 Composition of Electrical Supply in EEPCo Master Plan ................................... 2-31

Figure 2.3.5 Schematic Image of Electrical Supply Composition against Electricity

Demand in a day .......................................................................................... 2-31

Figure 2.3.6 CO2 Emission by Energy ..................................................................................... 2-32

Figure 3.1.1 Distribution of the African Rift Valley ................................................................... 3-1

Figure 3.1.2 Schematic Diagram for Development of the Red Sea Rift, the Aden Sea Rift,

and the Failed African Rift (MER) ................................................................ 3-2

Figure 3.4.1 SiO2-K2O+Na2O Diagram (TAS Diagram) ........................................................ 3-11

Figure 3.4.2 SiO2-K2O+Na2O Diagram in Olkaria Geothermal Field in Kenya ..................... 3-11

Figure 3.4.3 FeO-MgO-K2O+Na2O Diagram ......................................................................... 3-12

Figure 3.4.4 Distribution of geothermal manifestations in the Ethiopian Rift Valley .............. 3-20

Figure 3.4.5 Relationship between δD and δ18O of geothermal and surface waters ............... 3-24

Figure 3.4.6 Relative Cl, SO4, and HCO3 contents of geothermal and surface waters on

weight basis ................................................................................................. 3-25

Figure 3.4.7 Relative Na, K, and Mg contents of geothermal waters ...................................... 3-26

Figure 3.4.8 Comparison of temperatures calculated with geochemical thermometers for

the southwestern part of the Ethiopian Rift Valley ..................................... 3-28

Figure 3.4.9 Comparison of temperatures calculated with geochemical thermometers for

the northeastern part of the Ethiopian Rift Valley ........................................ 3-28

Figure 3.4.10 Relative He, Ar, and N2 contents of geothermal gases ...................................... 3-31

Figure 3.4.11 Relationship between 3He/4He and 4He/20Ne of geothermal gases ................. 3-32

Figure 3.4.12 Comparison of analytical results between GSE and the JICA study team ......... 3-33

Nippon Koei Co., Ltd. vi April 2015 JMC Geothermal Engineering Co., Ltd. Sumiko Resources Exploration & Development Co., Ltd.


Figure 3.5.1 Relations of Geothermal Sources, and Geothermal Reserves .............................. 3-35

Figure 3.5.2 Average Reservoir Temperature and Power Plant Type ....................................... 3-40

Figure 4.2.1 Outline of Process and Procedures of EIA in Ethiopia .......................................... 4-6

Figure 5.1.1 Flow of Multi-Criteria Analysis ............................................................................. 5-2

Figure 5.2.1 Well Simulation Results ......................................................................................... 5-6

Figure 5.2.2 Generation Cost of Geothermal and Hydropower Plants....................................... 5-9

Figure 5.2.3 Generation Cost of Geothermal and Other Power Plants .................................. 5-10

Figure 5.4.1 Tariff and Production Cost using Several Funds ................................................. 5-21

Figure 5.5.1 PPP Model Options and Tariff ............................................................................. 5-23

Figure 5.5.2 PPP Models for Geothermal Development in Ethiopia ....................................... 5-25

Figure 5.6.1 Geothermal Resource Direct Use in Ethiopia ...................................................... 5-28

Figure 5.6.2 Lindal Diagram .................................................................................................... 5-29

Figure 5.7.1 (R.1) Models of Geothermal Power Development in International Practice ......... 5-31

Figure 5.7.2 (R.2) Operation Option of GDC, Kenya ................................................................ 5-32

Figure 5.7.3 (R.3) Operation Mode of PNOC EDC in the Philippines ...................................... 5-34

Figure 5.7.4 (R.4) Geothermal Development Model before Privatization in Indonesia ............ 5-35

Figure 6.4.1 The location map of MT survey ............................................................................. 6-7

Figure 6.4.2 The location map of MT stations (Ayrobera site) .................................................. 6-8

Figure 6.4.3 The location map of MT stations (Boseti site) ....................................................... 6-9

Figure 6.4.4 The panel diagram of resistivity plan maps (Ayrobera site) ................................ 6-10

Figure 6.4.5 The panel diagram of resistivity plan maps (Boseti site) ..................................... 6-11

Figure 6.5.1 General Interpretation of Resistivity Structure in relation with Alteration

Minerals Occurrence and Temperature ........................................................ 6-12

Figure 6.5.2 Schematic Panel Diagram of Resistivity Distribution and Interpretation in

Ayrobera (Tendaho-2) .................................................................................. 6-15

Figure 6.5.3 Schematic Section of Ayrobera (Tendaho-2) ....................................................... 6-16

Figure 6.5.4 Schematic Panel Diagram of Resistivity Distribution and Interpretation in

Boseti ........................................................................................................... 6-18

Figure 6.5.5 Schematic Section of Boseti Geothermal Site ..................................................... 6-19

Figure 7.2.1 Preliminary Geothermal Reservoir Model in Tendaho-2 (Ayrobera) Site ............. 7-3

Figure 7.2.2 Preliminary Geothermal Reservoir Model (Section) in Tendaho-2 (Ayrobera) Site7-3

Figure 7.2.3 Test Well Drilling Plan in Tendaho-2 (Ayrobera) ................................................... 7-5

Figure 7.2.4 Schematic Section of Test Well Drilling in Tendaho-2 (Ayrobera) ........................ 7-5

Figure 7.3.1 Preliminary Geothermal Reservoir Model in Boseti site ....................................... 7-7

Figure 7.3.2 Preliminary Geothermal Reservoir Model (Section) in Boseti site ........................ 7-7

Nippon Koei Co., Ltd. vii April 2015 JMC Geothermal Engineering Co., Ltd. Sumiko Resources Exploration & Development Co., Ltd.


Figure 7.3.3 Test Well Drilling Plan in Boseti ............................................................................ 7-9

Figure 7.3.4 Schematic Section of Test Well Drilling in Boseti ................................................. 7-9

Figure 8.2.1 Startup Menu of G*BASE ..................................................................................... 8-2

Figure 8.3.1 2-D Geothermal Model (left) and 3-D Geothermal Model (right) of

the Aluto Area ................................................................................................ 8-4

Tables Table 1.2.1 Target Sites .............................................................................................................. 1-3

Table 1.2.2 Project Member ....................................................................................................... 1-4

Table 2.1.1 Growth and Transformation Plan (2010/11-2014/15) ............................................. 2-1

Table 2.1.2 GTP Targets of the Energy Sector .......................................................................... 2-2

Table 2.1.3 GTP Policy Matrix for Energy Sector .................................................................... 2-3

Table 2.2.1 Targets in the PASDEP/GTP Period 2005-2015 ..................................................... 2-4

Table 2.2.2 Electricity Sales (GWh: 2007-2012) ...................................................................... 2-9

Table 2.2.3 Generated Energy Sent out and Peak Demand (2002-2011) ................................ 2-10

Table 2.2.4 Energy Requirement Forecast in Categories (Reference Case) ............................ 2-11

Table 2.2.5 Peak Demand Forecast (Reference Case) ............................................................. 2-11

Table 2.2.6 Coincident Export Maximum Demand and Energy Forecast

(Reference Case) .......................................................................................... 2-12

Table 2.2.7 Energy Requirement and Peak Demand Forecast including Exports

(2012-2037) ................................................................................................. 2-12

Table 2.2.8 Installed Capacity of ICS and SCS, as of July 7, 2012 (2004 E.F.Y) ................... 2-15

Table 2.2.9 Power Production (GWh) ..................................................................................... 2-16

Table 2.2.10 Committed and Proposed Hydropower Plant ..................................................... 2-18

Table 2.2.11 Existing and Committed Wind Farm .................................................................. 2-19

Table 2.2.12 Candidate Sites for Solar Power Generation ...................................................... 2-19

Table 2.2.13 List of Proposed Biomass Energy Plants ............................................................ 2-20

Table 2.2.14 Proposed Waste-to-Energy Sites ......................................................................... 2-20

Table 2.2.15 List of Proposed Sugar Factories ........................................................................ 2-21

Table 2.2.16 Existing Transmission Line Length (km) ........................................................... 2-22

Table 2.2.17 Plan of New Substation and Transmission Line ................................................. 2-23

Table 2.2.18 Planned Interconnected Transmission Line ........................................................ 2-24

Table 2.2.19 Ehio-Kenya Electricity Highway Project ........................................................... 2-25

Table 2.2.20 Consumer Tariffs ................................................................................................ 2-26

Table 2.3.1 Existing Geothermal Development Plans ............................................................. 2-26

Table 2.3.2 Committed and Planned Geothermal Prospects.................................................... 2-29

Nippon Koei Co., Ltd. viii April 2015 JMC Geothermal Engineering Co., Ltd. Sumiko Resources Exploration & Development Co., Ltd.


Table 3.1.1 Stratigraphy of Main Ethiopian Rift (MER) ........................................................... 3-3

Table 3.2.1 Status of Detailed Survey at Each Site .................................................................... 3-4

Table 3.4.1 Schedule of Site Survey .......................................................................................... 3-8

Table 3.4.2 Methodology of Geological Analysis ...................................................................... 3-9

Table 3.4.3 Example of Site Reconnaissance Sheet ................................................................. 3-10

Table 3.4.4 XRF Analysis Results ............................................................................................ 3-13

Table 3.4.5 Mineral Occurrence by XRD ................................................................................. 3-14

Table 3.4.6 Summary of the site reconnaissance in the southwestern part of the Ethiopian

Rift Valley .................................................................................................... 3-16

Table 3.4.7 Summary of the site reconnaissance in the northeastern part of the Ethiopian

Rift Valley .................................................................................................... 3-17

Table 3.4.8 Analytical components .......................................................................................... 3-19

Table 3.4.9 Analytical methods ................................................................................................ 3-19

Table 3.4.10 Results of chemical and isotopic analysis for water samples .............................. 3-22

Table 3.4.11 Results of chemical and isotopic analysis for gas samples .................................. 3-23

Table 3.4.12 Calculated results of geochemical thermometers for geothermal waters ............ 3-27

Table 3.4.13 Calculated results of geochemical thermometers for geothermal gases .............. 3-29

Table 3.4.14 Estimation of ranges of reservoir temperature for a volumetric method ............. 3-30

Table 3.5.1 Comparison Between Eight Stages and AGRCC’s Categories ............................. 3-35

Table 3.5.2 Parameters for reservoir assessment ...................................................................... 3-38

Table 3.5.3 Determination of Plane Area of Geothermal Reservoir ......................................... 3-39

Table 3.5.4 Determination of Geothermal Reservoir Thickness .............................................. 3-39

Table 3.5.5 Average Reservoir Temperatures ........................................................................... 3-40

Table 3.5.6 Resource assessment ............................................................................................. 3-41

Table 3.5.7 Comparison of the results of the Prevailing method and Proposed method .......... 3-42

Table 3.5.8 Parameters Used for Reservoir Resource Assessment .......................................... 3-43

Table 4.1.1 The Target Sites ....................................................................................................... 4-2

Table 4.2.1 Major Regulations, Guidelines and Proclamations Applicable to

the Geothermal Energy Development Project ............................................... 4-3

Table 4.2.2 Draft Standards for Industrial Emission and Effluent Limits (Ethiopian EPA) ....... 4-7

Table 4.2.3 Draft Standards for Ambient Air Condition (Ethiopian EPA) ................................. 4-7

Table 4.2.4 National Noise Standard at Noise Sensitive Areas(Note) ....................................... 4-7

Table 4.2.5 EHS Guidelines for Emission Gas .......................................................................... 4-8

Table 4.2.6 EHS Guidelines for Effluent ................................................................................... 4-8

Table 4.3.1 Profile of Three Regions ....................................................................................... 4-12

Table 4.3.2 Natural, Historical and Cultural Heritages ............................................................ 4-14

Table 4.3.3 Distribution of sensitive environmental features surrounding the project ............. 4-14

Table 4.4.1 Environmental Characteristics of Geothermal Energy .......................................... 4-17

Nippon Koei Co., Ltd. ix April 2015 JMC Geothermal Engineering Co., Ltd. Sumiko Resources Exploration & Development Co., Ltd.


Table 4.4.2 Advantages of Geothermal Energy........................................................................ 4-17

Table 4.4.3 Comparison of Alternative .................................................................................... 4-18

Table 4.5.1 Environmental Categorization of Projects ............................................................. 4-19

Table 4.5.2 Environmental Scoping Checklist for the Project for Formulating Master Plan

on Development of Geothermal Energy in Ethiopia project ........................ 4-21

Table 4.5.3 Livelihood at the prospective sites ........................................................................ 4-23

Table 4.5.4 Statuses of Water Access in 15 Prospective Sites .................................................. 4-25

Table 4.5.5 Displacement and Resettlement/Land claim ......................................................... 4-25

Table 4.6.1 Mitigation Measures for EMP ............................................................................... 4-28

Table 4.6.2 Monitoring Plan for Geothermal Energy Development Project ............................ 4-29

Table 5.1.1 Development Target of the Master Plan .................................................................. 5-1

Table 5.2.1 Development Status and Geothermal Resource ...................................................... 5-3

Table 5.2.2 Economic Life ......................................................................................................... 5-5

Table 5.2.3 Plant Factor.............................................................................................................. 5-5

Table 5.2.4 Generation Costs of Candidate Hydropower Plants ................................................ 5-5

Table 5.2.5 Generation Costs of Non-Hydro and Non-Geothermal Plants ................................ 5-6

Table 5.2.6 Generation Costs of Geothermal Power Plants ....................................................... 5-8

Table 5.2.7 Ranking Order of the Geothermal Prospects ........................................................... 5-8

Table 5.2.8 Basic Assumptions Used for Economic Evaluation of Tendaho-2 (Ayrobera) ...... 5-11

Table 5.2.9 Ranking of Geothermal Power Plants and EIRR................................................... 5-11

Table 5.2.10 Required Length and Voltage of Transmission Line ........................................... 5-12

Table 5.2.11 Required Length and Topography of Access Road.............................................. 5-13

Table 5.2.12 Prioritization Order of the Geothermal Prospects ............................................... 5-14

Table 5.3.1 Simplified Geothermal Development Period ........................................................ 5-16

Table 5.3.2 Overall Schedule of Geothermal Power Development .......................................... 5-17

Table 5.3.3 Short-term Development Plan ............................................................................... 5-18

Table 5.3.4 Middle-term Development Plan ............................................................................ 5-19

Table 5.3.5 Long-term Development Plan ............................................................................... 5-20

Table 5.4.1 Possible Funds Loan Conditions ........................................................................... 5-21

Table 5.6.1 Present Status of Geothermal Direct Uses in the World and in Japan ................... 5-27

Table 5.6.2 Geothermal Direst Use .......................................................................................... 5-27

Table 5.6.3 Proposals for Direct Uses of Geothermal Resources in Ethiopia .......................... 5-30

Table 5.7.1 (R.1) Geothermal Power Stations Operational in Indonesia (as of 2015) ............... 5-36

Table 6.4.1 Summary of MT/TEM Survey at Boseti ................................................................. 6-5

Table 6.5.1 General Interpretation of Resistivity Structure in relation with Alteration

Mineral Occurrence and Temperature .......................................................... 6-12

Table 6.5.2 Existing Test Well Data in Dubti (Tendaho-1) ....................................................... 6-13

Nippon Koei Co., Ltd. x April 2015 JMC Geothermal Engineering Co., Ltd. Sumiko Resources Exploration & Development Co., Ltd.


Table 6.5.3 Interpretation of MT/TEM Survey Results with Alteration Mineral

Occurrence and Temperature in Tendaho-2 (Ayrobera) ............................... 6-14

Table 6.5.4 Interpretation of MT/TEM Survey Results with Alteration Mineral

Occurrence and Temperature in Boseti ........................................................ 6-17

Table 7.2.1 Summary and Interpretation of survey results and features for Geothermal Structural

Modeling ........................................................................................................ 7-1

Table 7.2.2 Characteristics of Geothermal Reservoir ................................................................... 7-2

Table 7.2.3 Tentative Target for Test Well Drilling in Tendaho-2 (Ayrobera) ............................ 7-4

Table 7.2.4 Tentative Specification of Test Well Drilling in Tendaho-2 (Ayrobera) .................. 7-4

Table 7.3.1 Summary and Interpretation of survey results and features for Geothermal Structural

Modeling ........................................................................................................ 7-6

Table 7.3.2 Characteristics of Geothermal Reservoir ................................................................. 7-6

Table 7.3.3 Tentative Specification of Test Well Drilling in Boseti ........................................... 7-8

Table 7.3.4 Tentative Specification of Test Well Drilling in Boseti ........................................... 7-8

Table 7.4.1 Reservoir Volume Estimated by Geothermal Conceptual Model .......................... 7-10

Table 7.4.2 Geothermal Potential Recalculated by Reservoir Volume ..................................... 7-10

Table 7.5.1 Types of Test Drilling ............................................................................................ 7-11

Table 8.2.1 Database Structure of “G*BASE” ........................................................................... 8-1

Table 8.2.2 Prospect IDs in G*BASE ........................................................................................ 8-2

Table 8.3.1 Geothermal Data in G*BASE ................................................................................. 8-3

Table 9.1.1 Proposed Additional Surface Survey and TG Wells ................................................ 9-2

Table 9.2.1 Proposed TOR of a Master Plan Project on Establishment of EEGeD ................... 9-4

Nippon Koei Co., Ltd. xi April 2015 JMC Geothermal Engineering Co., Ltd. Sumiko Resources Exploration & Development Co., Ltd.


Abbreviations

AFD French Development Agency

AfDB African Development Bank

AGRCC Australian Geothermal Energy Group Geothermal Code Committee

ARGeo African Rift Geothermal Development Facility

ASTER Advanced Spaceborne Thermal Emission and Reflection Radiometer

AUC Africa Union Commission

BGR Bundesanstalt für Geowissenschaften und Rohstoffe

CCGT Combined Cycle Gas Turbine

COD Commercial Operation Date

EAPP Eastern African Power Pool

EEA Ethiopian Energy Agency

EELPA Ethiopian Electric Light and Power Authority

EEP Ethiopian Electric Power

EEPCo Ethiopian Electric Power Corporation

EEU Ethiopian Electric Utility

EG Ethylene Glycol

EIA Environmental Impact Assessment

EIRR Economic Internal Rate of Return

EPA Environmental Protection Authority

ESIA Environmental and Social Impact Assessment

ESMF Environment and Social Management Framework

FS, F/S Feasibility Study

GHI Global Horizontal Irradiance

GIS Geographical Information System

GPS Global Positioning System

GRMF Geothermal Risk Mitigation Facility for Eastern Africa

GSE Geological Survey of Ethiopia

GSDP Geothermal Development Project

GTP Growth and Transformation Plan

HVAC high voltage alternate current

HVDC high voltage direct current

IAEA International Atomic Energy Agency

ICEIDA Iceland International Development Agency

ICS Inter-Connected System

IDA International Development Agency

IEE Initial Environmental Examination

IFC International Finance Corporation

Nippon Koei Co., Ltd. xii April 2015 JMC Geothermal Engineering Co., Ltd. Sumiko Resources Exploration & Development Co., Ltd.


IPP Independent Power Producer

JCC Joint Coordination Committee

JICA Japan International Cooperation Agency

KfW Kreditanstalt für Wiederaufbau

Ma Million age

MCA Multi-Criteria Analysis

MER Main Ethiopian Rift

MoM Ministry of Mines

MoFED Ministry of Finance and Economic Development

MoWIE Ministry of Water, Irrigation and Energy

MP, M/P Master Plan

MT Magneto-Telluric Method

NDF Nordic Development Fund

PALSAR Phased Array type L-band Synthetic Aperture Radar

PASDEP Plan for Accelerated and Sustainable Development to End Poverty

PPA Power Purchase Agreement

RG Reykjavik Geothermal

SCS Self-Contained System

SEA Strategic Environment Assessment

SREP Scaling up Renewable Energy Program

SWIR Short Wave Infrared Radiometer

TBD To be decided

TEM Transit Electro-Magnetic Method

TICAD Tokyo International Conference on African Development

TIR Thermal Infrared Radiometer

UEAP Universal Electricity Access Program

UNDP United Nations Development Programme

UNEP United Nations Environment Programme

USAID US Agency for International Development

VNIR Visible and Near-infrared Radiometer

WB The World Bank

WFB Wonji Fault Belt

XRD X-Ray Diffraction

XRF X-Ray Fluorescence

Nippon Koei Co., Ltd. xiii April 2015 JMC Geothermal Engineering Co., Ltd. Sumiko Resources Exploration & Development Co., Ltd.

The Project for Formulating Master Plan on Development of Geothermal Energy in Ethiopia Final Report

CHAPTER 1 BACKGROUND

1.1 Background The total installed capacity of electricity power plants in Ethiopia amounted to 2,100 MWe, as of

January 2010; more than 90% of such are of hydropower. Ethiopia intends to develop its huge

hydropower potential, estimated to be up to 45,000 MWe in the country, to satisfy the increasing

national demand as well as to export surplus electricity to surrounding countries.

However, yearly fluctuation of precipitation has become larger possibly due to global climate change,

which has aggravated the reliability of hydropower electricity generation. Economic and industrial

activities in the country are to be affected by the unexpected fluctuation of power supply that presently

depends heavily on hydropower.

Under such circumstances, the Ethiopia Electricity Power Cooperation (EEPCo) addresses the

development of indigenous energy such as geothermal and/or wind power, with recognition of the

importance of energy diversity and energy mixture.

Among other indigenous types of energy, geothermal energy has become more important as a base

load power, as well as the following: i) a substitute to fossil fuel being imported, ii) a major backup to

hydropower electricity supply, iii) a service to arid and semi-arid areas in the country where

hydropower is unavailable, and iv) contribution to the United Nations Framework Convention on

Climate Change (UNFCCC) effort of reducing global warming.

Geothermal potential survey was commenced in Ethiopia in 1969. Since then, step-by-step potential

surveys have identified more than 16 promising geothermal sites for electricity development. The total

geothermal potential is estimated at 5,000 MWe.

However, development stages of the sites vary (only two sites, i.e., Aluto-Langano site and Corbetti

site, are being developed towards commercial operation, whereas there are sites where development

has been suspended, as follows: i) after test well drillings (Tendaho-1 (Dubti) site and Gedemsa site),

ii) after slim hole drillings; and iii) after surface geological and geochemical surveys. Under this

condition, a priority comparison with reasonable datasets is required for geothermal development.

The Geological Survey of Ethiopia (GSE) requested the Government of Japan for technical assistance

in formulating a master plan for geothermal development including geothermal potential evaluation

and prioritization, and technical capacity building for geothermal development. In response to the

request, the Japan International Cooperation Agency (hereinafter referred to as “JICA”) conducted a

preparatory survey for survey planning in February 2013, that resulted in the Records of Discussion

(R/D) with Ethiopia for the implementation of “The Project for Formulating Master Plan on

Development of Geothermal Energy in Ethiopia” (hereunder referred to as “the Project”).


1-1

April 2015


Based on the R/D, JICA dispatched the JICA Project Team headed by Mr. TAKAHASHI Shinya of

Nippon Koei Co., Ltd., Japan to conduct the Project.

1.2 Objectives and Scope of Work of the Project

1.2.1 Objectives

The objectives of the Project are as follows:

1) To conduct geothermal surface survey for 161 geothermal prospects;

2) To prioritize geothermal prospects with a unique set of criteria with database construction;

3) To formulate the master plan for geothermal development based on the above; and

4) To contribute to capacity development of GSE under the process of formulating the master plan.

1.2.2 Counterpart and Relevant Organizations

The counterpart organization and the Joint Coordination Committee are as follows:

1) Counterpart:

Geological Survey of Ethiopia (GSE), Ministry of Mines of Ethiopia

2) Joint Coordination Committee (JCC)

i) Ethiopian Organizations

Director General of GSE / Chief Geologist of GSE

Director of Geothermal Resource Directorate, GSE

Representative from the Ministry of Mines (MoM)

Representative from the Ministry of Water, Irrigation and Energy (MoWIE)

Representative from the Ethiopian Electric Power (EEP)

Representative from the Ministry of Finance and Economic Development (MoFED)

ii) Japanese Organizations

Resident Representative of JICA Ethiopia Office

JICA Project Team

Other personnel concerned to be proposed by JICA

1 According to R/D (11 June 2013)


1-2

April 2015


iii) Observer

Representative from the Embassy of Japan

Note that EEPCo has been restructured into two companies: a) Ethiopia Electric Power

(EEP) responsible for power generation and supply, and b) Ethiopian Electric Utility (EEU) for

delivering electricity services (transmission, distribution, and sale of electric power). The EEP will be

managed by the Ethiopian CEO, whereas the EEU will be managed for two years by an Indian

company (Power Grid Corporation).

1.2.3 Target Sites

The target sites are listed in Table 1.2.1 below. The approximate locations are shown in the location

map at the beginning of this report.

Table 1.2.1 Target Sites

Geothermal Sites Prioritization /

Data base Remote Sensing

Site Survey

1 Dallol ☑ ☑ GSE 2 Tendaho-3 (Tendaho-Allalobeda) ☑ ☑ ☑ 3 Boina ☑ ☑ GSE 4 Damali ☑ ☑ GSE 5 Teo ☑ ☑ GSE 6 Danab ☑ ☑ GSE 7 Meteka ☑ ☑ ☑ 8 Arabi ☑ ☑ GSE 9 Dofan ☑ ☑ ☑ 10 Kone ☑ ☑ ☑ 11 Nazareth ☑ ☑ ☑ 12 Gedemsa ☑ ☑ ☑ 13 Tulu Moye ☑ ☑ - 14 Aluto-2 (Aluto-Finkilo) ☑ ☑ ☑ 15 Aluto-3(Aluto-Bobesa) ☑ ☑ ☑ 16 Abaya ☑ ☑ - (17) Fantale ☑ ☑ - (18) Boseti ☑ ☑ ☑ (19) Corbetti ☑ ☑ - (20) Aluto-1 (Aluto-Langano) ☑ ☑ - (21) Tendaho-1 (Tendaho-Dubti) ☑ ☑ - (22) Tendaho-2 (Tendaho-Ayrobera) ☑ ☑ ☑


☑:Target for the M/P formulation project GSE: The sites where GSE should undertake the site survey due to access and/or security issues. Source: Proposed by the JICA Project Team based on the R/D (11 June 2013) and subsequent discussions between GSE and the JICA Project Team

Among the 22 sites listed above, sites #01 to #16 are included in the R/D (11 June 2013), while sites

#17 to #22 are newly included in the Master Plan Formulation Project, as a result of the inception

report meeting held on 14 October 2013 at the GSE head office and other follow-up meetings.


1-3

April 2015


1.2.4 Member and Schedule of Project

Member list of this project is shown in Table 1.2.2.

Table 1.2.2 Project Member

Name Position Company

Shinya TAKAHASHI Team Leader / Geothermal Development Nippon Koei Co., Ltd.

Toshiaki HOSODA Acting Team Leader / Geology Nippon Koei Co., Ltd.

Tsukasa YOSHIMURA Geothermal Reservoir Evaluation Nippon Koei Co., Ltd.

Daisuke FUKUDA Geochemistry JMC Geothermal Engineering Co., Ltd.

Naoki KAWAHARA Electric Power Development / Database Nippon Koei Co., Ltd.

Nobuhiro MORI Economic Analysis Nippon Koei Co., Ltd. (KRI International Corp.)

Shinsuke SATO Socio-Environmental Assessment Nippon Koei Co., Ltd.

Masahiro TAKEDA Geophysical Survey-1 Sumiko Resources Exploration & Development Co., Ltd

Akira KIKUCHI Geophysical Survey-2 Sumiko Resources Exploration & Development Co., Ltd

Yasushi MOMOSE Donor Coordination-1 / Geothermal Reservoir Evaluation-2

Nippon Koei Co., Ltd.

Masako TERAMOTO Donor Coordination-1 / Geochemistry -2 Nippon Koei Co., Ltd.



1-4

April 2015



2-1

April 2015

CHAPTER 2 ELECTRICITY DEVELOPMENT PLAN

2.1 Growth and Transformation Plan

2.1.1 Overview

The latest government development plan is the Five-year Growth and Transformation Plan (GTP) for

the period 2010/11-2014/15. The GTP has been prepared with clear objectives and targets through

wide public participation at both the federal and regional levels. The Council of Ministers and the

House of People’s Representative have adopted the GTP as the national planning document of the

country for the period 2010/11-2014/15. The GTP’s main objectives, strategies, and targets are clearly

set out in the document. During the GTP period, special emphasis will be given to agricultural and

rural development, industry, infrastructure, social and human development, good governance, and

democratization.

The Ministry of Finance and Economic Development is responsible for preparing, implementing, and

monitoring the GTP. The visions, objectives, and strategic pillars are summarized in Table 2.1.1.

Development programs that will be implemented in the five-year GTP period will have a strong focus

on improving the quality of public services provided. Thus, special emphasis is given to investments in

infrastructure and in the social and human development sectors. It is clear that implementation of the

GTP will require mobilization of considerable financial and human resources, especially for

infrastructure development. For this reason, mobilization of domestic financial and human resources,

as well as improvements in domestic savings, are considered to be critical.

Table 2.1.1 Growth and Transformation Plan (2010/11-2014/15)

Factor Description Ethiopia’s vision guiding the GTP

“to become a country where democratic rule, good governance, and social justice reign upon the involvement and free will of its peoples, and once extricating itself from poverty to reach the level of a middle-income economy as of 2020-2023.”

Vision on economic sectors “building an economy which has a modern and productive agricultural sector with enhanced technology and an industrial sector that plays a leading role in the economy, sustaining economic development and securing social justice and increasing per capita income of the citizens so as to reach the level of those in middle-income countries.”

Objectives 1. Maintain at least an average real gross domestic product (GDP) growth rate of 11% and attain the millennium development goals (MDGs); 2. Expand and ensure the qualities of education and health services and achieve MDGs in the social sector; 3. Establish suitable conditions for sustainable nation building through the creation of a stable democratic and development state; and 4. Ensure the sustainability of growth by realizing all the above objectives within a stable macroeconomic framework.

Strategic pillars 1. Sustaining rapid and equitable economic growth, 2. Maintaining agriculture as major source of economic growth, 3. Creating conditions for the industry to play key role in the economy, 4. Enhancing expansion and quality of infrastructure development, 5. Enhancing expansion and quality of social development, 6. Building capacity and deepen good governance, and 7. Promote gender and youth empowerment and equity.

Source: GTP (2010/11-2014/15)



2-2

April 2015

2.1.2 Energy Sector Plan

The strategic directions of the energy sector are development of renewable energy, expansion of

energy infrastructure, and creation of an institutional capacity that can effectively and efficiently

manage such energy sources and infrastructure. During the GTP period, the gap between the demand

for and supply of electricity will be minimized.

The main objective of the energy sector is to meet the demand for energy in the country by providing

sufficient and reliable power supply that meets international standards at all time. This objective will

be achieved by accelerating and completing the construction of new hydropower plants, as well as

geothermal plants, and strengthening the existing transmission lines to provide improved access to

rural villages all over the country. An additional objective is to export power to the neighboring

countries. Modernizing the distribution system will also be considered to reduce power losses.

The main targets of the energy sector are summarized in Table 2.1.2.

Table 2.1.2 GTP Targets of the Energy Sector

Description of Target 2009/10 2014/15

1. Hydroelectric power generating capacity (MW) 2,000 10,000

2. Total length of distribution lines (Km) 126,038 258,000

3. Total length of rehabilitated distribution lines (Km) 450 8,130

4. Reduce power wastage (%) 11.5 5.6

5. Number of consumers with access to electricity 2,000,000 4,000,000

6. Coverage of electricity services (%) 41 75

7. Total underground power distribution system (Km) 97 150

Source: GTP (2010/11-2014/15)

The implementation strategies for power generation and transmission are set out as follows:

For power generation: Ethiopia has a potential to generate 45,000 MW of hydroelectric power and

5,000 MW of geothermal power. However, currently only 2,000 MW has been developed. It is planned

to increase this level of generated power by four times. The implementation strategies are: (i) to

promote a best mix of energy sources by developing hydro, geothermal, and other renewable energies

including wind and solar power; (ii) to prevent power losses and promote proper utilization of energy;

(iii) to reduce unit costs of power generation investments and operations; and (iv) to provide electricity

at affordable prices.

For power transmission: To ensure a reliable electricity supply and transmit the electric power

efficiently and economically to consumers, construction of a reliable transmission and distribution

networks is essential. To this end, due emphasis will be given in the Universal Electrification Access

Program to construct new transmission lines and connect them to the national grid as economically as

possible and to reduce power losses.

The GTP policy matrix for the energy sector, which stipulates who will do what by when and will be

verified by how, is set out as follows:



2-3

April 2015

Table 2.1.3 GTP Policy Matrix for Energy Sector

MoWIE: Ministry of Water, Irrigation, and Energy

Source: GTP (2010/11-2014/15) (modified by the JICA Project Team)

2.2 Overview of Power Sector

2.2.1 Policy, Laws, Regulations, and Strategy

The Transitional Government of Ethiopia released its first National Energy Policy in March 1994. This

is still in force as the policy of the Government of Ethiopia and is currently being revised. It aims to

address household energy problems by promoting agro-forestry, increasing the efficiency with which

biomass fuels are utilized, and facilitating the shift to greater use of modern fuels. Furthermore, the

policy states that the country will rely mainly on hydropower to increase its electricity supply, and also

take advantage of geothermal, solar, wind, and other renewable energy resources, where appropriate. It

also refers to the need to encourage energy conservation in the industry, transport, and other major

energy-consuming sectors, to ensure that energy development is economically and environmentally

sustainable.

The Plan for Accelerated and Sustained Development to End Poverty (PASDEP) was presented as a

five-year (2005/06-2009/10) development strategy by the Government of Ethiopia in 2006, which

aims to become a middle income country in 20-30 years. The PASDEP had set its target in the energy

sector to increase the access rate from 16% (2005/06) to 50% (2009/10) by the augmentation of energy

generation from 791 MW to 2,218 MW and the expansion of the grid to 13,054 km. Energy loss was

also planned to be reduced from the current level of 19.5% to the international average of 13.5%

during the PASDEP period. The total cost for these plans was estimated to be ETB 51 billion

(equivalent to USD 5.3 billion) for five years which was almost equal to the annual national budget.

Base year Implementing Means of(2009/10) 10/11 11/12 12/13 13/14 14/15 Agency Verification

Increased in electricpower users

Number of consumers with access toelectricity (in million)

2.03 2.13 2.33 3.70 3.30 4.00

Increased in electricpower distribution

Coverage of electricity services (%) 41 50 55 65 70 75

Total length of distribution lines (Km) 126,038 1E+05 1E+05 2E+05 2E+05 3E+05

Total length of rehabilitated distributionlines (Km)

450 967 3,258 5,694 8,130 8,130

reduce power wastage of powertransmission lines (%)

11.0 10.8 8.5 5.6 5.6 5.6

Total underground power distributionsystem (Km)

97 53

High voltage (500 kV) electric grid lineconstructed (Km)

434 434 434

High voltage (400 kV) electric grid lineconstructed (Km)

710 710 714 1,082 1,377 1,377

Voltage grid lines with 230, 132, 66 kVconstructed (Km)

10,730 11,397 12,954 13,604 14,404 15,189

Proportion of rehabilitated distribution sub-stations (%)

50 100

Reduce power wastage of powertransmission and distribution sub-stations

5.34 4.5 4.0 4.0 4.0 3.0

Power generating capacity (MW) 2,000 2,045 2,582 3,117 5,054 10,000

Electric power produced (GWh) 7,653 7,923 10,576 12,140 19,234 32,656

Increased electricpower generationand production

Increased in generationand produced electricpower

MoWIEMoWIEannualreport

MoWIE MoWIEannualreport

Modernizing thedistribution andtransmissionsystem, so as toreduce powerlosses tointernationalbenchmark levels

Increased inconstructed electricsub-stations andgridlines their quality

MoWIEMoWIEannualreport

Objective Output IndicatorAnnual Targets (20**/**)

Increase qualityelectric powersupply servicecoverage

Increased inconstruction of electricdistribution station



2-4

April 2015

Following PASDEP, the GTP mentioned in Section 2.1 is the current national policy for the period

2010/11 – 2014/15 and has targets for energy sector to increase the installed capacity by 8,000 MW of

renewable energy resources. Table 2.2.1 presents the targets of PASDEP and GTP.

Table 2.2.1 Targets in the PASDEP/GTP Period 2005-2015

Item 2005/06 PASDEP

2005/06-2009/10 2012

GTP 2010/11-2014/15

Installed Capacity 791MW 2,218 MW (+1,427MW) 2,168 MW 10,000 MW Electrification Rate 16% 50% (+34%) 17% 75% Length of Transmission/Distribution Line

- 13,054km 12,461 km 258,000 km

Electricity Loss 19.5% 13.5% - 5.6%

Source: PASDEP/GTP (summarized by the JICA Project Team)

The Ethiopian Electric Power Corporation (EEPCo), which was the national electricity utility and in

charge of power generation plan, completed the “Ethiopian Power System Expansion Master Plan” in

February 2014. The objective of the study is to update the least cost Power System Expansion Program

for the development of Ethiopia's generation and transmission systems for the next 25 years

(2013–2037).

Based on the national policies above new hydropower plants have been commissioned and a number

of power plants using renewable energy resource has been committed for construction in the next ten

years. The Prime Minister of Ethiopia, Hailemariam Desalegn, also mentioned the necessity of

Africa’s transformation and enhanced the importance of energy development in his speech given on 29

September 2013 in New York. He also stated that Ethiopia will develop around 80,000 MW of hydro,

geothermal, wind, and solar power over the next 30 years, not just for Ethiopia, but for neighboring

countries as well.

On the other hand, the Government of Japan agreed to the Yokohama Declaration 2013 that prioritizes

investment promotion for renewable energy including hydro, solar, and geothermal, in the Fifth Tokyo

International Conference on African Development (TICAD V) held on 3 June 2013. And also Japan’s

Prime Minister, Shinto Abe, expressed his intention to resume the Japanese Yen Loan and conveyed

his expectation that its first project would be the expansion of Aluto-Langano Geothermal Power Plant.

He also expressed his interest in the development potential of geothermal energy in Ethiopia.

2.2.2 Power Sector Institutions

The power sector is managed by the national government. There are five major institutions engaging

in the sector, namely: (i) Ministry of Mines (MoM), (ii) Geological Survey of Ethiopia (GSE), (iii)

Ministry of Water, Irrigation and Energy (MoWIE), (iv) Ethiopian Electric Power (EEP) and Ethiopian

Power Utility (EEU), and (v) Independent Power Producers (IPPs). Functionality-wise, the MoM and

MoWIE undertake policy-making and regulation while GSE conducts geothermal exploration and EEP,

EEU, and IPPs undertake construction and operation of power supply system (generation and

transmission and distribution) as shown in Figure 2.2.1.



2-5

April 2015


Figure 2.2.1 Organizational Chart of Power Sector in Ethiopia

(1) Geological Survey of Ethiopia (GSE)

GSE is responsible for geothermal exploration as part of the mineral exploration of the country. GSE

was established under the Ministry of Mines and has been involved in geothermal exploration since

the work started with reconnaissance surveys in the Ethiopian Rift Valley between 1969 and 1973

funded by the United Nations Development Programme (UNDP). It is currently responsible for all

scientific exploration works including the drilling and testing of wells. EEP then takes over the power

station construction and operation. This is the model used for the development of the Aluto- Langano

and Tendaho fields.

Figure 2.2.2 and Figure 2.2.3 shows organization chart of GSE and Geothermal Resource Exploration

& Assessment Directorate. GSE has eight technical sections, which are managed by the chief geologist

under the director general. Geothermal Resource Exploration & Assessment Directorate has

responsibility about geothermal resource exploration in GSE.

Ethiopian Pow

er C

orporation (EE

PCo)

Geological Survey of Ethiopia(GSE)

Ministry of Water, Irrigation and Energy (MoWIE)

Ethiopian Energy Agency (EEA)

Ethiopian Electric Utility (EEU)

Policy and Regulation

Generation and Transmission

Distribution and Supply

Production Right

Development Right

Power Purchase Agreement (PPA) IPPs

Export

Prospecting Right

Exploration Right

Ethiopian Electric Power (EEP)

Split in Feb. 2014

Ministry of Mines (MoM)



2-6

April 2015

Source: GSE

Figure 2.2.2 GSE Organization Chart

Source: GSE

Figure 2.2.3 Organization Chart of Geothermal Section

(2) Ministry of Mines (MoM)

MoM is the ministry responsible for geothermal development in Ethiopia through GSE headed by its

Director General. There is no staff at the ministry dealing specifically with geothermal activities.

(3) Ministry of Water, Irrigation and Energy (MoWIE)

MoWIE is the responsible organization of the Government of Ethiopia that is responsible for the

country’s energy sector development and expansion. MoWIE has two sections, namely: energy section

and water supply section and the energy section has six divisions and has jurisdiction over Ethiopian

Energy Agency (EEA), Ethiopian Electric Power (EEP) and Ethiopian Electric Utility (EEU). Energy

related directorates within MoWIE are responsible for energy policy drafting, implementation follow

up and supervision. They are also responsible for conducting research and studies including

development and promotion of rural energy-efficient technologies.

Director General

Human ResourceManagement & Development

Support Directorate

Planning, Monitoring & Evaluation Process

GeoscienceData

Directorate

Change ManagementDirectorate

Information Communication

Technology Directorate

Gender Mainstreaming

Directorate

Legal Affairs

Directorate

Public Relation & Communication

Directorate

HIV AID Focal

Directorate

Procurement & Finance, Property Administration & General

Services, Drilling Equipment & Vehicles Maintenance

& Transport Support DirectorateAudit

Directorate

Ethics Liaison Officer

Chief Geologist Hundie Melka

Basic Geoscience

Mapping Directorate

Mineral Exploration

& Evaluation Directorate

GroundwaterResource

AssessmentDirectorate

Geo-hazards Investigation Directorate

Geothermal Resource

Exploration & Assessment Directorate(37 officers)

GeoscienceLaboratory

Centre

Drilling Service Centre

Scientific Equipment

Engineering,Repair &

Maintenance Centre

Geothermal Resource Exploration &Assessment Directorate

Reservoir Engineering Section Chief: Akalewold Seifu Feleke

Quota: 9 Occupied: 6

Geology Section Chief: Selamawit Worku


Geochemistry Section Chief: Asfaw Teclu


Geophysics Section Chief: Yiheis Kebede


Director Solomon Kebede



2-7

April 2015

(4) Ethiopian Energy Agency (EEA)

The Electricity Proclamation No. 86/1997 of June 1997 paved the way for the establishment of the

Ethiopian Electricity Agency as an autonomous federal government organization. The Ethiopian

Energy Authority (EEA), which was established in 2000, replaced the Ethiopian Electricity Agency in

2013 by the Energy Proclamation No.810/2013, and is tasked to oversee EEP/EEU and controls the

investments in the country. EEA is responsible for the regulation of operations in the electricity supply

sector including licensing and ensuring safety and quality standards and has also set prices for the

private and state power distributors.

To regulate electricity generation, transmission, distribution, and sale of electricity, EEA is responsible

for setting the tariffs and regulating and supervising access by private operators to the electricity grid,

which includes the approval of power purchase agreements (PPAs).

(5) Ethiopian Electric Power (EEP)/ Ethiopian Electric Utility (EEU)

Ethiopian Electric Power Corporation (EEPCo) was the only government body that is responsible for

planning, investing, commissioning, and operating electricity generation, transmission, distribution,

and sale of electricity throughout Ethiopia. The predecessor, Ethiopian Electric Light and Power

Authority (EELPA) was established in 1956 and rebuilt as EEPCo in 1997 by Regulation Number

18/1997.

As shown in Figure 2.2.4, EEPCo was split into two public enterprises in December 2013, i.e., namely

Ethiopian Electric Power (EEP) and Ethiopian Electric Utility (EEU). The aim of this restructuring

was to create modern entities capable of providing efficient, reliable, and high-quality services. EEP is

responsible for construction and operation of the power generation and transmission while EEU is

responsible for construction and operation of power distribution and sales. EEU which is in charge of

the electricity delivery has already awarded a consortium of three Indian companies a two-year and

half management contract for USD 21 million in August 2013. The companies have responsibility for

increasing the efficiency of the operation, distribution and sale of electric power and also support the

efficiency increase and capacity building of generation operation and transmission operation of EEP.

Geothermal development projects including on-going projects of Aluto-Langano and Corbetti are

managed by the Generation Projects section in EEP and overall electric generation planning is

conducted by the Planning section of the Corporate Functions in Figure 2.2.4.



2-8

April 2015

Source: World Bank

Figure 2.2.4 EEP and EEU Organization Chart

2.2.3 Power Demand Forecast

For the purpose of formulating the master plan on development of geothermal energy, the demand

forecast for power given by EEP was reviewed. The latest forecast is conducted by former EEPCo in

the study of “Ethiopian Power System Expansion Master Plan (hereinafter EEPCo master plan)” based

on the records up to 2011.

(1) Past Growth of Power Demand

Table 2.2.2 and Figure 2.2.5 show the historical energy sales from 2002 to 2011. Total electricity sales

has increased with high growth rates of around 5% to 25%, and reached 4,069.68 GWh in 2011,

although sales temporarily decreased in 2009 due to a worldwide economic crisis. The electricity

consumer is divided into four categories based on tariff category as shown in Figure 2.2.6, namely,

domestic (1,632.86 GWh, 40%), commercial (955.56 GWh, 23%), street light (25.75 GWh, 1%),

industrial LV (711.47 GWh, 18%), and industrial HV (744.04 GWh, 18%). By category, because of the

increase in number of connections with an electrification growth in the Universal Electricity Access

Program (UEAP), domestic power demand has greatly increased and has tripled in the past decade.



2-9

April 2015

Table 2.2.2 Electricity Sales (GWh: 2007-2012)

Source: Ethiopian Power System Expansion Master Plan, EEPCo (modified by the JICA Project Team)

Source: Ethiopian Power System Expansion Master Plan, EEPCo (arranged by the JICA Project Team)

Figure 2.2.5 Electrical Sales and Number of Customers


Figure 2.2.6 Electrical Sales Growth by Category and Share in 2011 (GWh)

No. Category Type 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011

Sales (GWh) 568.66 583.92 637.94 704.58 759.76 973.11 1,087.42 1,191.68 1,350.34 1,632.86

Domestic No.Connection 535,254 571,975 637,016 739,009 820,514 923,390 1,177,627 1,250,802 1,263,655 1,381,963

kWh/Connection 1,062 1,021 1,001 953 926 1,054 923 953 1,069 1,182

Sales (GWh) 381.95 391.32 444.81 507.70 556.73 638.24 788.08 625.12 717.42 955.56

Commercial No.Connection 79,731 83,806 91,863 104,331 114,281 125,853 166,233 165,351 166,166 202,475

kWh/Connection 4,791 4,669 4,842 4,866 4,872 5,071 4,741 3,781 4,317 4,719

Sales (GWh) 12.55 16.60 21.18 28.35 32.13 44.80 44.94 18.79 20.38 25.75

Street light No.Connection 985 1,139 1,267 1,546 1,782 2,105 2,455 2,635 1,959 3,013

kWh/Connection 12,743 14,574 16,717 18,338 18,030 21,283 18,305 7,131 10,403 8,546

Sales (GWh) 301.02 369.65 346.88 401.46 494.06 489.16 654.01 519.24 562.93 711.47

Large Industry LV No.Connection 7,957 8,204 8,871 10,036 11,422 12,083 18,432 18,104 14,682 21,071

kWh/Connection 37,831 45,057 39,103 40,002 43,255 40,483 35,482 28,681 38,342 33,765

Sales (GWh) 330.92 313.96 364.37 386.83 468.05 404.80 576.00 543.01 599.70 744.04

Large Industry HV No.Connection 96 93 101 122 131 154 200 169 114 163

kWh/Connection 3,447,106 3,375,914 3,607,624 3,170,738 3,572,901 2,628,571 2,880,000 3,213,077 5,260,526 4,564,663

Sales (GWh) 1,595.10 1,675.45 1,815.18 2,028.92 2,310.73 2,550.11 3,150.45 2,897.84 3,250.77 4,069.68Growth Rate (%) - 5.04% 8.34% 11.78% 13.89% 10.36% 23.54% -8.02% 12.18% 25.19%No.Connection 624,023 665,217 739,118 855,044 948,130 1,063,585 1,364,947 1,437,061 1,446,576 1,608,685

kWh/Connection 2,556.16 2,518.65 2,455.87 2,372.88 2,437.14 2,397.66 2,308.11 2,016.50 2,247.22 2,529.82

Sub Total

4

5

1

2

3

1,595.101,675.451,815.18

2,028.922,310.73

2,550.11

3,150.452,897.84

3,250.77

4,069.68

0

200,000

400,000

600,000

800,000

1,000,000

1,200,000

1,400,000

1,600,000

1,800,000

0.00

500.00

1,000.00

1,500.00

2,000.00

2,500.00

3,000.00

3,500.00

4,000.00

4,500.00

5,000.00

2002 2003 2004 2005 2006 2007 2008 2009 2010 2011

Sales (GWh)

No.Connection

Sale

s (G

Wh)

No.

of C

onne

ctio

n

0.00

200.00

400.00

600.00

800.00

1,000.00

1,200.00

1,400.00

1,600.00

1,800.00

2002 2003 2004 2005 2006 2007 2008 2009 2010 2011

Domestic

Commercial

Street light

Large Industry LV

Large Industry HV

Sale

s (G

Wh)

1,632.86, 40%

955.56, 23%25.75, 1%

711.47, 18%

744.04, 18%

Domestic

Commercial

Street light

Large Industry LV

Large Industry HV



2-10

April 2015

Table 2.2.3 shows the electrical energy sold and generated for the years 2002 to 2011 and the system

peak load and load factor. In 2011, an electric power of 4,954 GWh was generated by all power plants

with total installed capacity of 2,167 MW in Ethiopia. Energy loss varying from 10%–20% from 2002

to 2011 has been comparatively high because of transmission distribution loss. System peak demand

has also increase more than twice in the past decade and was recorded 914 MW.

Table 2.2.3 Generated Energy Sent out and Peak Demand (2002-2011)


Based on the Eastern Africa Power Pool (EAPP) framework and the power purchase agreements

(PPAs) between Ethiopia and its neighboring countries, Ethiopia has exported electricity to

neighboring countries such as Djibouti, Kenya and Sudan. Summary of the agreement regarding the

power purchase is shown below.

- First 400 MW to Kenya (Around 3,000 GWh)

- 100 MW to Djibouti (Around 570 GWh)

- First 100 MW to Sudan (Around 880 GWh)

- First 200 MW to South Sudan/Egypt (Around 1,300 GWh)

- First 200 MW to Tanzania (Around 1,399 GWh)

(2) Power Demand Forecast

As mentioned above, the power demand has increased with a high growth rate in the past decade. The

power demand is expected to increase in the future not only due to increase in domestic consumers but

also new consumers such as railway constructions, large-scale irrigation facilities, new industries, and

electricity exports. The EEPCo master plan conducted the electricity forecast for the period from 2013

to 2037 and covers reference, high and low cases.

The EEPCo master plan study has conducted the forecast for each category such as domestic,

commercial, industrial, and irrigation using a combination of regression analysis load forecast model

and end-user models.

The total energy requirement in Ethiopia is forecasted from 6,425 GWh in 2012 to 111,388 GWh in

2037 as shown in Table 2.2.4. It was forecasted to have high growth. In particular, the growth for the

first ten years is very high because of the large growth in the industrial and irrigation sectors, and the

new electrical demand of the new railway.

2002 2003 2004 2005 2006 2007 2008 2009 2010 2011

Energy Sales (GWh) 1,595.10 1,675.45 1,815.18 2,028.92 2,310.73 2,550.11 3,150.45 2,897.84 3,250.77 4,069.68

Generation Sent-Out (GWh) 1,784 2,028 2,278 2,540 2,845 3,269 3,502 3,665 3,946 4,954Energy Loss (%) 10.6% 17.4% 20.3% 20.1% 18.8% 22.0% 10.0% 20.9% 17.6% 17.9%

System Maximum Demand (MW) 391 405 454 521 587 623 675 673 767 914

System Load Factor (%) 52% 57% 57% 56% 55% 60% 59% 62% 59% 62%



2-11

April 2015

Table 2.2.4 Energy Requirement Forecast in Categories (Reference Case)

Source: Ethiopian Power System Expansion Master Plan, EEPCo (arranged by JICA Project Team)

The peak demand in Ethiopia was estimated from the total sales forecast. The peak demand will reach

21,731 MW in 2037 from 1,186 MW in 2012 in the reference case. The averaged growth rate is

12.3%.

Table 2.2.5 Peak Demand Forecast (Reference Case)


Domestic UAEP CommercialStreet

LightingLV

IndustrialHV

IndustrialNew

IndustryTransport(Railway)

Irrigation Sugar Total Sales Total LossesGenaration

Sent-out

2012 1,912 22 1,193 33 711 744 302 - - 5 4,922 1,503 6,4252013 2,192 206 1,350 35 711 744 1,036 - - 49 6,323 1,910 8,2332014 2,358 401 1,529 37 711 744 2,376 - 156 101 8,413 2,513 10,9262015 2,512 605 1,736 39 711 744 4,303 404 389 101 11,544 3,143 14,6872016 2,648 821 1,928 41 711 744 6,723 633 778 101 15,128 3,595 18,7232017 2,761 1,051 2,143 44 711 744 9,729 938 1,167 101 19,389 3,972 23,3612018 2,853 1,300 2,383 46 711 744 12,638 1,062 1,561 101 23,399 4,097 27,4962019 2,926 1,556 2,646 48 711 744 14,805 1,185 2,214 101 26,936 4,312 31,2482020 2,982 1,845 2,937 51 711 744 16,461 1,477 2,866 101 30,175 4,790 34,9652021 3,025 2,144 3,255 54 711 744 18,393 1,642 3,519 101 33,588 5,287 38,8752022 3,058 2,502 3,602 57 1,072 1,153 20,324 1,818 4,172 101 37,859 5,909 43,7682023 3,082 2,936 3,980 60 1,466 1,602 20,324 2,162 4,824 101 40,537 6,273 46,8102024 3,100 3,460 4,389 64 1,896 2,095 20,324 2,373 5,477 101 43,279 6,639 49,9182025 3,114 4,039 4,833 67 2,362 2,633 20,324 2,583 6,130 101 46,186 7,024 53,2102026 3,124 4,708 5,313 71 2,867 3,219 20,324 2,849 6,782 101 49,358 7,441 56,7992027 3,131 5,455 5,833 75 3,412 3,855 20,324 3,135 7,435 101 52,756 7,883 60,6392028 3,137 6,266 6,393 79 3,998 4,542 20,324 3,456 8,088 101 56,384 8,425 64,8092029 3,141 7,128 6,996 83 4,625 5,282 20,324 3,789 8,740 101 60,209 8,997 69,2062030 3,144 8,029 7,642 88 5,294 6,076 20,324 4,123 9,393 101 64,214 9,595 73,8092031 3,146 8,939 8,331 92 6,006 6,924 20,324 4,542 10,046 101 68,451 10,228 78,6792032 3,148 9,871 9,065 98 6,758 7,825 20,324 4,994 10,699 101 72,883 10,890 83,7732033 3,149 10,822 9,842 103 7,551 8,779 20,324 5,448 11,351 101 77,470 11,576 89,0462034 3,150 11,789 10,668 109 8,384 9,785 20,324 5,923 11,967 101 82,200 12,283 94,4832035 3,150 12,772 11,536 115 9,253 10,841 20,324 6,398 12,583 101 87,073 13,011 100,0842036 3,151 13,773 12,444 121 10,157 11,943 20,324 6,880 13,199 101 92,093 13,761 105,8542037 3,151 14,485 13,391 128 11,093 13,088 20,324 7,331 13,816 101 96,908 14,480 111,388

Year

Sales Forecast (GWh)

Max Demandat Comsumer Level (MW)

Power Loss(%)

Max Demand(MW)

Power Load Factor

(%)2012 847 28.6% 1,186 61.8%2013 1,087 28.3% 1,516 62.0%2014 1,436 27.9% 1,992 62.6%2015 1,951 26.1% 2,641 63.5%2016 2,543 23.8% 3,335 64.1%2017 3,229 21.4% 4,107 64.9%2018 3,876 19.2% 4,795 65.5%2019 4,499 18.1% 5,496 64.9%2020 5,092 18.1% 6,219 64.2%2021 5,704 18.1% 6,962 63.7%2022 6,439 18.0% 7,848 63.7%2023 6,976 18.0% 8,504 62.8%2024 7,527 18.0% 9,176 62.1%2025 8,108 17.9% 9,881 61.5%2026 8,738 17.9% 10,644 60.9%2027 9,410 17.9% 11,455 60.4%2028 10,123 17.9% 12,335 60.0%2029 10,870 18.0% 13,256 59.6%2030 11,647 18.1% 14,213 59.3%2031 12,461 18.1% 15,215 59.0%2032 13,306 18.1% 16,254 58.8%2033 14,176 18.2% 17,322 58.7%2034 15,063 18.2% 18,410 58.6%2035 15,973 18.2% 19,526 58.5%2036 16,906 18.2% 20,669 58.5%2037 17,777 18.2% 21,731 58.5%

Max Demand

Year



2-12

April 2015

As mentioned above, the Government of Ethiopia has agreed electricity purchase with neighboring

countries. The maximum demand and energy sales of the export were forecasted as shown below.

Energy export sales are forecast to grow from 1,445 GWh in 2013 to 35,303 GWh by 2037, and the

total demands (MW) of exports are forecast to grow from 140 MW in 2012 to 4,080 MW by 2037.

Table 2.2.6 Coincident Export Maximum Demand and Energy Forecast (Reference Case)


Table 2.2.7 presents the overall load forecast including exports in each case at the generation sent-out

level. Figure 2.2.7 shows the total energy generation while Source: Ethiopian Power System Expansion

Master Plan, EEPCo (arranged by JICA Project Team)

Figure 2.2.8 shows the peak demand. Energy generation and peak demand in reference case are

forecasted to reach 146,691 GWh and 25,761 MW by 2037, respectively.

Table 2.2.7 Energy Requirement and Peak Demand Forecast including Exports (2012-2037)

Djibouti SudanSudan

andEgypt

Kenya Kenya II Tanzania Total Djibouti SudanSudan

andEgypt

Kenya Kenya II Tanzania Total

(MW) 100 100 200-3100 400 200-1200 200-400 100 100 200-3100 400 200-1200 200-400Load factor 65% 100% 75% 85% 75% 75% 65% 100% 75% 85% 75% 75%

2012 40 100 0 0 0 0 140 395 68 0 0 0 0 4632013 65 100 0 0 0 0 165 569 876 0 0 0 0 1,4452014 65 100 0 0 0 0 165 569 876 0 0 0 0 1,4452015 65 100 150 0 0 0 315 569 876 1,314 0 0 0 2,7592016 65 100 150 0 0 0 315 569 876 1,314 0 0 0 2,7592017 65 100 450 340 0 0 955 569 876 3,942 2,978 0 0 8,3652018 65 100 450 340 0 0 955 569 876 3,942 2,978 0 0 8,3652019 65 100 600 340 0 0 1105 569 876 5,256 2,978 0 0 9,6792020 65 100 600 340 0 150 1255 569 876 5,256 2,978 0 1,314 10,9932021 65 100 900 340 150 150 1705 569 876 7,884 2,978 1,314 1,314 14,9352022 65 100 900 340 150 150 1705 569 876 7,884 2,978 1,314 1,314 14,9352023 65 100 1200 340 150 300 2155 569 876 10,512 2,978 1,314 2,628 18,8772024 65 100 1200 340 300 300 2305 569 876 10,512 2,978 2,628 2,628 20,1912025 65 100 1500 340 450 300 2755 569 876 13,140 2,978 3,942 2,628 24,1332026 65 100 1500 340 450 300 2755 569 876 13,140 2,978 3,942 2,628 24,1332027 65 100 1650 340 600 300 3055 569 876 14,454 2,978 5,256 2,628 26,7612028 65 100 1650 340 750 300 3205 569 876 14,454 2,978 6,570 2,628 28,0752029 65 100 1650 340 900 300 3355 569 876 14,454 2,978 7,884 2,628 29,3892030 65 100 1950 340 900 300 3655 569 876 17,082 2,978 7,884 2,628 32,0172031 65 100 1950 340 900 300 3655 569 876 17,082 2,978 7,884 2,628 32,0172032 65 100 2175 340 900 300 3880 569 876 19,053 2,978 7,884 2,628 33,9882033 65 100 2250 340 900 300 3955 569 876 19,710 2,978 7,884 2,628 34,6452034 65 100 2250 340 900 300 3955 569 876 19,710 2,978 7,884 2,628 34,6452035 65 100 2325 340 900 300 4030 569 876 20,367 2,978 7,884 2,628 35,3022036 65 100 2325 340 900 300 4030 569 876 20,367 2,978 7,884 2,628 35,3022037 65 100 2325 340 900 300 4030 569 876 20,367 2,978 7,884 2,628 35,302

Coincident Export Maximum Demand (MW) Energy Export (GWh)

Year



2-13

April 2015




Figure 2.2.7 Energy Requirement Forecast including Exports (2012-2037)

Reference High Low Reference High Low

2012* 6,906 6,906 6,906 1,378 1,378 1,378

2013 9,680 10,763 9,034 1,681 1,884 1,5752014 12,371 14,171 11,272 2,157 2,483 1,9752015 17,447 21,490 14,393 2,956 3,560 2,4992016 21,482 26,462 18,376 3,650 4,392 3,1392017 31,729 38,469 23,700 5,062 6,037 3,938

2018 35,862 43,582 28,411 5,750 6,872 4,6512019 40,929 50,918 32,045 6,601 8,037 5,2702020 45,960 56,932 34,760 7,474 9,080 5,7982021 53,811 66,454 39,073 8,667 10,525 6,5062022 58,703 73,037 42,220 9,553 11,685 7,094

2023 65,689 82,171 44,006 10,659 13,113 7,5102024 70,110 88,210 45,748 11,481 14,206 7,9272025 77,343 97,294 48,848 12,636 15,671 8,5042026 80,933 103,018 50,790 13,399 16,788 8,9642027 87,401 112,572 52,838 14,510 18,373 9,448

2028 92,885 120,831 55,044 15,540 19,854 9,9702029 98,597 129,718 59,968 16,611 21,440 10,8122030 105,827 141,098 66,263 17,868 23,331 11,8172031 110,698 149,902 68,742 18,870 24,955 12,3922032 117,761 160,036 71,300 20,134 26,756 12,983

2033 123,693 172,152 73,929 21,277 28,808 13,5872034 129,127 182,951 76,591 22,365 30,726 14,1932035 135,386 196,419 79,296 23,556 32,972 14,8092036 141,157 208,659 82,045 24,699 35,105 15,4332037 146,691 221,594 84,803 25,761 37,341 16,061


Total Energy Requirement (GWh) Total Peak Demand (MW)Year

17,447

45,960

77,343

110,698

135,386146,691

21,490

56,932

97,294

149,902

196,419

221,594

6,90614,393

34,76048,848

68,74279,296 84,803

0

50,000

100,000

150,000

200,000

250,000

2012

*

2013

2014

2015

2016

2017

2018

2019

2020

2021

2022

2023

2024

2025

2026

2027

2028

2029

2030

2031

2032

2033

2034

2035

2036

2037

Reference High LowGWh

Year

Power Generation



2-14

April 2015



Figure 2.2.8 Peak Demand Forecast including Exports (2012-2037)

2,956

7,474

12,636

17,868

23,55625,761

3,560

9,080

15,671

23,331

32,972

37,341

1,3782,499

5,798

8,504

11,817

14,80916,061

0

5,000

10,000

15,000

20,000

25,000

30,000

35,000

40,000

2012

*

2013

2014

2015

2016

2017

2018

2019

2020

2021

2022

2023

2024

2025

2026

2027

2028

2029

2030

2031

2032

2033

2034

2035

2036

2037

Reference High Low

Year

MW

Peak Demand



2-15

April 2015

2.2.4 Power Generation Planning

(1) Existing Power Plant

There are two electrical supply systems in Ethiopia, namely, on-grid Inter-Connected System (ICS)

and off-grid Self-Contained System (SCS). Table 2.2.8 shows the installed capacity for both ICS and

SCS. According to Facts in Brief 2011/12 of EEPCo and the EEPCo master plan study, total capacities

of ICS and SCS are 2,140.20 MW and 26.80 MW, respectively in 2012, with a total capacity of 2,167

MW. The number and type of power plants in ICS are: 12 hydropower (1,940.6 MW), 13 diesel (112.3

MW), 1 geothermal (7.3 MW), and 2 wind, which generate about 6,000 GWh. Table 2.2.9 shows the

power generation in the past five years. Because of new hydropower plants such as Gigel Gibe II, Tana

Beles, Tekeze and Amerti Neshe, power generation has been largely increasing for the past two years.

The Aluto-Langano Geothermal Power Plant is the only geothermal power plant in Ethiopia at present,

which is a binary generation of 7.3 MW commissioned in 1999. Due to leak in the heat exchanger

tubes, the plant was shut down 18 months after starting its operation. The plant was rehabilitated but

current generation was decreased to 5 MW. As of April 2014, the plant has not been in production due

to maintenance problem.



2-16

April 2015

Table 2.2.8 Installed Capacity of ICS and SCS, as of July 7, 2012 (2004 E.F.Y)

Source: Facts in Brief 2011/12, EEPCo

No. Power Plant Capacity (MW) Initial Year

ICS Generation Plant

Hydro 1940.61 Koka 43.2 1960

2 Tis Abay I 11.4 1964

3 Awash II 32.0 1966

4 Awash III 32.0 1971

5 Finchaa 134.0 1973/2003

6 Meleka Wakana 153.0 1988/refurb in 2014

7 Tis Abay II 73.0 2001

8 Gilgel Gibe 184.0 2004

9 Gilgel Gibe II 420.0 2010

10 Tana Beles 460.0 2010

11 Tekeze 300.0 2010

12 Amerti Neshe 98.0 2011

Geothermal 7.31 Aluto Langano 7.3 1999

Diesel 112.31 Alemaya 2.3 1958

2 Ghimbi 1.1 1962/1984

3 Dire Dawa (mu) 4.5 1965

4 Axum 3.2 1975/1992

5 Shire 0.8 1975/1991/1995

6 Nekempt 1.1 1984

7 Mekelle 5.7 1984/1991/1993

8 Adigrat 2.5 1992/1993/1995

9 Adwa 3.0 1998

10 Kaliti 14.0 2004

11 Dire Dawa 38.0 2004

12 Awash 7 Kilo 35.0 2004

13 Jimma 1.1

Wind 81.01 Ashegoda 30.0 Jan/2012

2 Adama I 51.0 Mar/2012

ICS Total 2,141.2

SCS Generation Plant

Hydro 6.151 Yadot 0.35

2 Sor 5.00

3 Dembi 0.80

Diesel 20.65 Isolated diesel power plants

SCS Total 26.8

(ICS+SCS) Total 2,168.0



2-17

April 2015

Table 2.2.9 Power Production (GWh)

Source: Facts in Brief 2011/12, EEPCo

(2) Planned and Committed Power Plants (Non-geothermal) Hydropower

Ethiopia has a very high hydropower potential available for power generation. In the past five years

(2009-2013), four hydro power plants with a total capacity of around 1,200 MW were commissioned

and tripled the overall capacity in Ethiopia. There are 12 existing plants with installed capacity of

around 1,800 MW and one plant has been under refurbishment. Figure 2.2.9 shows the location map of

existing, committed, and proposed hydropower plants. Three plants, i.e., Gilgel Gibe III, Genale Dawa

III, and Grand Renaissance, are under construction. If their constructions are completed in five years

as scheduled, the total installed capacity of hydropower will be around 10,000 MW in 2018. The

progress of the three hydropower plants under construction is mentioned below.

Gilgel Gibe III: The construction of the dam, which is 243m high, was started in 2006, and is 88%

complete as of October 2014 and expected to reach 92% by the end of this fiscal year. The first of ten

System Generation Type 2007/08 2008/09 2009/10 2010/11 2011/12

Hydro 3,353.60 3,277.14 3,503.79 4,922.00 6,239.29

Diesel 133.13 381.78 407.41 14.00 0.00

Geothermal - 13.87 23.61 18.00 7.98

Wind - - - - 29.40

Sub-total 3,486.73 3,672.79 3,934.81 4,954.00 6,276.67

Hydro 16.49 19.23 20.11 9.00 1.84

Diesel 28.48 35.77 26.15 17.00 11.07

Sub-total 44.97 55.00 46.26 26.00 12.91

Hydro 3,370.09 3,296.37 3,523.90 4,931.00 6,241.13

Diesel 161.61 417.55 433.56 31.00 11.07

Geothermal - 13.87 23.61 18.00 7.98

Wind - - - - 29.40

Total 3,531.70 3,727.79 3,981.07 4,980.00 6,289.58

SCS

ICS

Total

0.00

1,000.00

2,000.00

3,000.00

4,000.00

5,000.00

6,000.00

7,000.00

2007/08 2008/09 2009/10 2010/11 2011/12

Hydro

Diesel

Geothermal

Wind

Production (G

Wh)



2-18

April 2015

planned turbines was scheduled to start generating 187 MW in September 2014, but due to financial

problem, the project has been delayed. The following nine turbines are expected to take about a year

for the dam to be fully operational and generate 1,870 MW.

Genale Dawa III: The construction was started in mid-2012 and around 25% complete in 2013 and

60% as of October 2014. It is expected to be fully completed by 2015 and to provide 254 MW.

Grand Renaissance: The construction of the Grand Ethiopian Renaissance Dam was started since

April 2011. The dam with 6,000 MW of installed capacity will be the largest hydroelectric power plant

in Africa when completed, as well as the 8th largest in the world. The construction of the dam

progressed to around 20% at the end of 2013, and was at 40% complete as of October 2014. The first

stage of the dam will be operational from June 2015 and will produce 700 MW of electricity. The rest

of the units will be completed and a total of 6,000 MW will be generated in 2018.


Figure 2.2.9 Location Map of Existing, Committed, and Proposed Hydropower Plants

There have been many hydropower plant schemes proposed over the years. There are 28 schemes that

contribute to the overall capacity of around 12,400 MW. Table 2.2.10 shows the list of committed and

proposed hydropower plants. In the new EEPCo master plan study, the averaged levelized cost of each

proposed hydropower plant was estimated, and was used in ranking the candidate hydropower plants.

Adiss Ababa



2-19

April 2015

Table 2.2.10 Committed and Proposed Hydropower Plant


Wind Power

The Ethiopian government has planned to generate up to 890 MW of wind energy by the end of the

Growth and Transformation Plan (GTP) period. In 2009, the first wind farm in Ethiopia was

constructed in Adama, which has 34 x 1.5 MW wind turbines. The Ashegoda Wind Farm, which is 10

km from Mekelle, was completed in 2013. The total installed capacity of the Ashegoda Wind Farm

will be 120 MW. The Ashegoda Project, which costs about EUR 210 million, was funded by the

French bank- BNP Paribas, the French Development Agency, and EEPCo. The Adama II Wind Farm

Project, an extension of the Adama Project, is in progress. EEPCo signed an agreement with the

Chinese GCOC Company and Hydrochina Company for the construction of a wind farm with 102 x

1.5 MW wind turbines, with a total capacity of 153 MW. The project costs USD 340 million, and the

Chinese Export & Import Bank provides a soft loan.

Ethiopia has an estimated 10 GW of potential wind capacity. The Hydrochina Corporation

collaborated with the Ministry of Water and Energy and formulated the Wind Power and Solar Energy

Inst.(MW)

Avil. Cap.(MW)

Ave. Gen.(GWh)

Hydro - Under Construction 8124.0 6274.0 21826.01 Gilgel Gibe III (enters 2014) 748.0 427.0 2148.0 2014

- Gilgel Gibe III (enters 2015) 1122.0 640.0 3222.0 20152 Genale Dawa III 254.0 250.0 1695.0 20153 Grand Renaissance (enters 2015) 500.0 413.0 1230.0 2014

- Grand Renaissance (enters 2017) 5500.0 4544.0 13531.0 2018Hydro - Candidate 12406.9 12062.6 59279.3

1 Beko Abo 935.0 935.0 6632.2 2022

2 Genji 216.0 214.0 910.2 2020

3 Upper Mendaya 1700.0 1700.0 8582.3 2023

4 Karadobi 1600.0 1493.9 7857.2 2021

5 Geba I + Geba II 371.5 343.6 1709.4 2020

6 Genale VI 246.0 237.2 1532.4 2020

7 Gibe IV 1472.0 1409.6 6146.4 2020

8 Upper Dabus 326.0 326.0 1460.3 2020

9 Sor II 5.0 4.8 38.5 2017

10 Birbir R 467.0 443.7 2724.1 2020

11 Halele + Werabesa 436.0 417.2 1972.8 2020

12 Yeda I + Yeda II 280.0 275.9 1089.4 2020

13 Genale V 100.0 100.0 574.6 2020

14 Gibe V 660.0 603.5 1904.9 2020

15 Baro I + Baro II 645.0 645.0 2614.3 2020

16 Lower Didessa 550.0 550.0 975.6 2020

17 Tekeze II 450.0 450.0 2720.7 2020

18 Gojeb 150.0 134.2 561.7 2020

19 Aleltu East 189.0 173.8 804.1 2020

20 Tams 1000.0 1000.0 6057.2 2020

21 Abu Samuel 6.0 6.0 15.7 2020

22 Aleltu West 264.6 262.7 1067.3 2020

23 Wabi Shebele 87.8 86.5 691.0 2020

24 Lower Dabus 250.0 250.0 637.0 2020

Power Plant CO D



2-20

April 2015

Master Plan in 2012 with financial support from the Chinese government. The master plan study

identified 51 candidates for wind farm located mainly on high terrain.

Table 2.2.11 Existing and Committed Wind Farm

No. Wind Farm Capacity

(MW) Generation

(GWh) Annual

Load Factor COD

Existing Wind Farm 171 428 1 Adama I 51 150 33.6% 2012

2 Ashegoda (enters 2012） 30 70 26.5% 2012

- Ashegoda (enters 2014） 90 208 26.4% 2014

Committed Wind Farm 153 424 1 Adama II 153 424 31.6% 2015

Total 324 852


Solar Power

In general, Ethiopia is rich in solar radiation resource, as it is located on a low latitude region with

approximately perpendicular incidence of sunshine. But currently, solar power is only used for off-grid

systems such as telecommunications equipment in rural areas. In rural electrification schemes, there is

a plan to use solar power. However, there is no scheme to connect ICS, and no plant has been

committed so far.

Some studies, including the Wind Power and Solar Energy Master Plan conducted by the Hydrochina

Corporation, has conducted the analysis and identified some potential site for photovoltaic power

plants. Table 2.2.12 summarizes the candidates examined in the EEPCo master plan study. The study

expected 100 MW of solar power generation per plant.

Table 2.2.12 Candidate Sites for Solar Power Generation

No. Solar Power Plant GHI

(kWh/m2)Yield

(kWh/kWp/year)Energy Output

MWh/year CF (%)

Solar PlantSize (MW)

Candidate Site

1 Mekele 2391.2 20,542 205,420 23.4% 100

2 Jijiga 2379.7 20,184 201,840 23.0% 100

3 Addis Ababa 1934.5 16,639 166,390 19.0% 100

4 Border Ethiopia – Kenya 1903.6 15,561 155,610 17.8% 100

5 Border Ethiopia – Somalia 2086.0 16,697 166,697 19.1% 100

GHI: Global Horizontal Irradiance, CF: Capacity Factor


Biomass Energy

Ethiopia has utilized biomass such as fuel wood, residue of agricultural crops, and animal manure for

basic energy instead of electricity. Two biomass plants, namely Bamza and Meikasedi thermal power

plants, have been planned as candidate plants. As the biomass plants use bagasse as fuel, these are

unavailable for four months during the off-crop season. Table 2.2.13 summarizes the proposed

biomass energy plants.



2-21

April 2015

Table 2.2.13 List of Proposed Biomass Energy Plants

Biomass Power Plant Bamza Meikasedi

Rated Power (MW) 120 138

Nominal Output (MW) 60 60

First Year of Operation 2016 2016

Fuel Type Wood Fuel

Bagasse Prosopis Bagasse


Waste Power Generation

EEPCo finalized a turnkey contract with the Cambridge Industries Ltd. to design and construct a 50

MW capacity waste-to-energy plant in the Repi area, Addis Ababa in 2013. This will be the first

waste-to-energy plant in Ethiopia. And also, Cambridge Industries Ltd. has conducted detailed

feasibility studies throughout Ethiopia to recommend future projects in various cities including Dire

Dawa, Adama, Mekelle, Gonder, Behar Dar, Hawasa, and Jimma. Table 2.2.14 summarizes the

committed waste-to-energy plants.

Table 2.2.14 Proposed Waste-to-Energy Sites

Item Addis Ababa

Waste Energy Plant

Rated Power (MW) 50

Nominal Output (MW) 20

First Year of Operation 2015

Fuel Type Municipal solid waste and

selected industrial waste


Sugar Factories

The Ethiopian sugar factories have planned to sell their surplus electricity to the grid. The electricity is

generated by the process of burning bagasse. Power generation is conducted only in the period from

October to May because of bagasse production.



2-22

April 2015

Table 2.2.15 below shows the installed capacity and energy which can be exported to the grid in each

factory.



2-23

April 2015

Table 2.2.15 List of Proposed Sugar Factories

Sugar Factories Installed Capacity

(MW)

Export (MW)

Exported Energy (GWh)

COD

Wenji 30 16 77 2013

Finchaa 31 10 48 2013

Tendaue/Ende 120 70 337 2015

Beles 1 30 20 96 2015

Beles 2 30 20 96 2015

Wolkayit 133 82 395 2015

Omo Kuraz 1 60 20 96 2015

Kessem 26 16 77 2015

Beles 3 30 20 96 2016

Omo Kuraz 2 60 40 193 2016

Omo Kuraz 3 60 40 193 2016

Omo Kuraz 4 60 40 193 2017

Omo Kuraz 5 60 40 193 2017

Omo Kuraz 6 60 40 193 2019

Total 474 2,283 Source: Ethiopian Power System Expansion Master Plan, EEPCo (arranged by the JICA Project Team)

Thermal Power Plant

At present, there are 11 thermal power plants using heavy fuel oil and light fuel oil as shown in Table

2.2.8. There is no committed power plant using gas and oil. The new EEPCo master plan proposed to

operate gas turbines, combined cycle gas turbines (CCGT), and diesel power plants from 2018.

To correspond to the increasing power demand from 2030 or later, thermal power plants will be

needed because the hydropower and geothermal potential could not cover the demand even though all

of them are being developed.

2.2.5 Transmission Planning

(1) Existing and Committed Transmission Lines

Most of the power plants have been connected with the ICS to the consumers though transmission

lines of 400 kV, 230 kV, 132 kV, 66 kV, and 45 kV. Table 2.2.16 presents the total length of the

existing transmission lines and Figure 2.2.10 shows the map of existing and planned transmission

network.

There are many areas where ICS does not connect to/in Ethiopia. SCS, which has supplied electricity

to such areas not connected to ICS, is now starting to sequentially connect to ICS in these past few

years.

EEP (former EEPCo) has connected the transmission line to towns and villages at its expense.

However, the distribution line to houses and offices has to be connected individually at the expense of

the end-user, therefore leaving many poor people unable to pay for connection and access to

electricity.



2-24

April 2015

Table 2.2.16 Existing Transmission Line Length (km)

No. Voltage Level Single Circuit Double Circuit Total 1 400 kV 621 63 684 2 230 kV 3,376 1,607 4,983 3 132 kV 4,509 133 4,641 4 66 kV 1,902 1,902 5 45 kV 243 9 252

Total 10,650 1,811 12,461 (Source: EEP, summarized by the JICA Project Team)

Source: EEP 2014

Figure 2.2.10 Existing and Committed Electrical Grid in Ethiopia

(2) Universal Electricity Access Program (UEAP)

The Universal Electricity Access Program (UEAP) was started by EEPCo from 2005/06 as part of the

power sector development program to embody the targets of PASDEP, which aimed at connecting a

total of 6,878 towns and villages to the grid, provide energy supply to 24 million people, and attain an

electrification rate of 50% in 2015. Also, it aimed to increase the energy generation capability to 6,386

GWh by 2010. The total cost of the UEAP was estimated at ETB 8.8 billion and the World Bank (WB)

is financing part of it.

Although the aspired target was not fully met, electricity generation increased by 53% from 2,587.2

GWh in 2005 to 3,981.07 GWh in 2010. However, the production increase did not keep pace with the

grid extension activities. Transmission lines increased, from a total length of 8,003.93 km in 2006 to



2-25

April 2015

10,884.24 km in 2010, while distribution lines’ total length even quadrupled from 33,000 km in 2005

to 126,038 km in 2010.

(3) Transmission Expansion Plan

Transmission expansion plan was developed in the EEPCo master plan study based on the demand

forecast and generation plan mentioned above. The transmission expansion plan was considered to

connect the candidate power plants meeting the electrical demand forecast in two stages, i.e.,

short-term from 2013 to 2020 and long-term from 2021 to 2037.

New 118 transmission substations, 77 substation reinforcements and 13,550 km of new transmission

lines (66 to 500 kV) are planned in the short-term plan, and new 78 transmission substations, 41

substation reinforcements and 9,257 km of new transmission line (132 to 400 kV) as shown in Table

2.2.17.

Table 2.2.17 Plan of New Substation and Transmission Line



Figure 2.2.11 presents the development plan of major transmission line from 230 to 500 kV by 2020

and 2037 and location of the geothermal prospects. The transmission line of 500 kV is limited to the

grand renaissance dam to Addis Ababa and the international connection to Sudan based on the cost

comparison analysis. The main network will comprise 230 and 400 kV transmission lines.

This development plan includes the generation plan of committed geothermal project including

Aluto-1 (Aluto-Langano) and Corbetti. Most of the other geothermal prospects in this project are

located along the existing and planned networks which also run along the Rift Valley.

Year New SubstationNew SubstationReinforcements

Transmission Lines(km)

2013 11 10 2,3432014 9 3 1,1672015 48 43 4,1882017 25 6 2,4702020 25 15 3,383

Short-Term: Total 118 77 13,5512025 24 8 2,4222030 24 17 2,8092037 29 30 3,185

Long-Term: Total 77 55 8,416



2-26

April 2015


Figure 2.2.11 Expansion Network Plan (left: short-term, right: long-term)

(4) International Connection Eastern African Power Pool (EAPP)

According to the generation plan mentioned above, Ethiopia is expected to have a capacity of over

13,000 MW by year 2020 and over 24,000 MW by year 2030. Excess generation capacity in Ethiopia

will be available for export to neighboring countries of the Eastern Africa Community. For this

purpose, the EAPP has undertaken an interconnection program schematically represented in Table

2.2.18.

The program has already been partially implemented from the Ethiopia side interconnecting with

Sudan through a 230 kV transmission line, operational for the supply of 100 MW, to be increased in

the future, and the interconnection with Djibouti through a 230 kV transmission line.

Table 2.2.18 Planned Interconnected Transmission Line

No. Connecting Voltage (kV) Capacity (MW) Date 1 Tanzania-Kenya 400 1520 2015 2 Tanzania-Uganda 220 700 2023 3 Uganda-Kenya 220 440 2023 4 Ethiopia-Kenya DC500 2000 2016 5 Ethiopia-Sudan 500 2 x1600 2016 6 Egypt-Sudan DC600 2000 2016 7 Ethiopia-Kenya DC500 2000 2020 8 Ethiopia-Sudan 500 1600 2020 9 Egypt-Sudan DC600 2000 2020

10 Ethiopia-Sudan 500 1600 2025 11 Egypt-Sudan DC600 2000 2025



2-27

April 2015

Source: EAPP

Ethio-Kenya Electricity Highway Project

The transmission line construction in the Ethio-Kenya Highway Project under Phase 1 of the Regional

Eastern Africa Power Pool Program was started in 2013, and is expected to be completed by 2018. The

governments of Ethiopia and Kenya have received loans from the African Development Bank (AfDB),

and the Government of Kenya has applied for a loan from the French Development Agency (AFD) for

the project cost. The total project cost is about USD 1.3 billion. The project is mainly comprised of a

1,045 km, ± 500 kV high voltage direct current (HVDC) over-head transmission line from

Wolayita-Sodo in Ethiopia to Logonot in Kenya. EEP and the Kenya Electricity Transmission

Company Limited intend to manage the project jointly. Table 2.2.19 shows the project contents.

Table 2.2.19 Ehio-Kenya Electricity Highway Project

No. Location

Size Number Form To

1 Wolaita Sodo ss Logonot ss 500 kV HVDC line 1066 km

2 Converter at each ss 1000 MW

3 Gilgel Gibe III Wolaita Sodo ss 400 kV HVAC line 55 km

4 Logonot ss Ishinya ss 400 kV HVAC line 80 km

5 Synchronous Condenser at Lognot ss 200 MVA 1

ss: sub-station, HVDC: high voltage direct current, HVAC: high voltage alternate current

Source: EEP, arranged by the JICA Project Team

(5) Power Loss

The power loss in Ethiopia is around 20%, which is higher than the international average of 12–13%.

According to EEP, most of the loss happened during the distribution from the national grid to end

users. Therefore, WB has financed some projects of a Swedish company that promotes efficiency in

Addis Ababa and a French company that automates the distribution system.

2.2.6 Financing and Tariff

(1) Electric Power Selling

Table 2.2.20 shows the published consumer tariffs in Ethiopia for 50 years from 1959 to 2003. The

domestic tariff is reduced to around ETB 0.47/kWh (equivalent to around USD 0.03/kWh) with a large

amount of subsidies, so that the poverty group can have access to electricity.

It is suggested that the rich who utilize more electricity should bear more of the costs by progressive

tariffs, which would still ensure the access of the poor whose utilization of electricity is minimal. This

also contributes to the increment of finance of the EEP, which is necessary to expand the service to

achieve the ambitious targets of the GTP.



2-28

April 2015

Table 2.2.20 Consumer Tariffs

LV: Low Voltage、HV: High Voltage


2.3 Geothermal Power Development

2.3.1 Existing Geothermal Development Plans

There are two existing geothermal development plans as shown in Table 2.3.1, i.e., one by GSE and

one by the EEPCo master plan study. These existing plans need to be improved since they do not

reflect recent activities of several donors including the power purchase agreement (PPA) between

EEPCo and Reykjavík Geothermal agreed in September 2013 for Corbetti Geothermal Development

of 500 MW to 1,000 MW. Likewise in the EEPCo master plan, all candidate geothermal power plants

are sized in multiples of 100 MW capacities for simplicity without considering the site specific

potential and installation plans based on forecast demand.

Table 2.3.1 Existing Geothermal Development Plans

Source: *1GSE, 2010: (Tendaho indicates Tendaho-1 (Dubti) and -3(Allalo Beda) according to interview with GSE)

*2Ethiopian Power System Expansion Master Plan, EEPCo, February 2014: (Tendaho includes Tendaho-1, -2 and -3.

Aluto-Langano includes Aluto-1, -2 and -3)

(arranged by the JICA Project Team)

1952-1964 1988-1989 1990 1991-1998 1999-2003EEPCo ICS SCS EEPCo ICS SCS EEPCo ICS SCS EEPCo EEPCo EEPCo EEPCo EEPCo

1 House Hold 0.1250 0.1250 0.1250 0.1250 0.1425 0.1513 0.1468 0.1425 0.1513 0.1468 0.1772 0.2809 0.3897 0.47352 Commercial 0.0750 0.1250 0.1650 0.1436 0.1525 0.1975 0.1735 0.3436 0.4146 0.3774 0.3653 0.4301 0.5511 0.67233 Street　Light 0.1100 0.1500 0.1285 0.1100 0.1500 0.1285 0.3322 0.4146 0.3711 0.3333 0.3087 0.3970 0.48434 Small Industry 0.1333 0.1733 0.1520 0.1333 0.1733 0.1520 0.2232 0.4597 0.32035 LV 0.0475 0.0875 0.0645 0.0625 0.1175 0.0857 0.2232 0.4397 0.3133 0.2563 0.3690 0.4736 0.57786 HV 15kV 0.0288 0.0780 0.0474 0.0588 0.0588 0.2029 0.2029 0.2341 0.2597 0.3349 0.40867 HV 132kV 0.2416 0.3119 0.3805

Total Flat Rate 0.0968 0.0824 0.1241 0.1011 0.1027 0.1556 0.1165 0.2341 0.3500 0.2735 0.2645 0.3086 0.4020 0.4900

1965-1971 1972-1978 1979-1987DescriptionHistorical Flat Tariff Rate (Birr/kWh) EFY

Site

2014 Aluto Langano 52015 52016 Aluto Langano II 70 752017 752018 Tendaho 100 175

Corbetti 75 ~ 300 250 ~ 475

Tulu Moye 40 290 ~ 515Dofan Fantale 60 350 ~ 575

2019 350 ~ 5752020 Abaya 100 450 ~ 675

Year Total(MW)

Installed Capacity(MW)

GSE*1

IntalledUnits

SiteTotal(MW)

2014 0 Aluto Langano 52015 0 52016 0 52017 0 52018 2 Coebetti 200

2019 1 Corbetti 3002020 2 Corbetti 500

2021 2 Aluto Langano 7002022 2 Tendaho 9002023 0 9002024 0 9002025 3 Tendaho, Abaya 12002026 4 Tendaho, Abaya, Tulu Moya 16002027 0 16002028 5 Dofan, Fantale, Tulu Moya, Gedemsa 21002029 2 Tendaho 23002030 2 Teo 25002031 3 Corbetti 28002032 3 Teo, Gedemsa 31002033 3 Aluto Langano, Dofan, Fantale 34002034 3 Tulu Moya, Dofan, Fantale 37002035 5 Corbetti, Dofan, Fantale, Dallol 42002036 4 Dallol, Teo 46002037 4 Teo, Abhe 5000

EEPCo*2

Year



2-29

April 2015

The EEPCo master plan formulated an overall power generation plan by plant type as shown in Figure

2.3.1 while corresponding energy is presented in Figure 2.3.2. Comparing the electric demand, the

reserve margin will exceed 120% in 2017 with the commissioning of the Grand Ethiopian Renaissance

Dam, but from 2017, it will decline to around 25% by 2037.

Hydropower generation is the largest source of energy and capacity throughout the period. Following

hydropower, geothermal power becomes the next largest energy producer, followed by combined cycle

gas turbine (CCGT) in 2037. Hydropower and geothermal will occupy around 50% and 25% of total

installed capacity, and around 55% and 33% of total power generation in 2037, respectively. In the

EEPCo master plan, wind and solar power generation are planned prior to geothermal power, which is

mainly planned to be developed after 2025, when most of candidate hydropower plants are completed.

Source: Ethiopian Power System Expansion Master Plan, EEPCo, February 2014

Figure 2.3.1 Installed Capacity and Reserve Margin



2-30

April 2015

Source: Ethiopian Power System Expansion Master Plan, EEPCo, February 2014

Figure 2.3.2 Energy Generation by Plant Type

2.3.2 Committed Geothermal Power Development Plans

In this master plan study, considering the latest information on donor involvements and GSE plan,

existing and committed geothermal sites are ranked in priority order of development.



2-31

April 2015

Table 2.3.2 summarizes the committed geothermal prospects. The expansion of Aluto-Langano

Geothermal Power Plant has been implemented to boost its capacity to 70 MW from the previous 7 MW.

The four drilling wells up to 2,500 m deep have been started and aim to generate 77 MW of power by

2018. The cost of the project will be covered by the financial assistance from the Government of Japan

and WB as well as the Government of Ethiopia.

In October 2013, Reykjavík Geothermal signed a PPA with EEPCo for the Corbetti geothermal

development of up to 1,000 MW in installed capacity. Reykjavík Geothermal will start drilling up to five

wells with an initial 20 MW output.

The Geothermal Risk Mitigation Facility (GRMF) agreed on 3 March 2014 to give the Ethiopia

Ministry of Mines, a USD 976,872 grant in order to conduct a study in Dofan and Corbetti, Ethiopia.

GRMF was established by the African Union Commission in collaboration with the German Federal

Ministry for Economic Cooperation and Development and the EU-Africa Infrastructure Trust Fund via

KfW Entwicklungs.



2-32

April 2015

Table 2.3.2 Committed and Planned Geothermal Prospects

MP S No.

Site Planned Capacity

and COD Status of Commitment


25 MW 2017 ICEIDA/NDF assists surface survey including MT survey.

19 Corbetti

20 MW 80 MW

200 MW 200 MW

2015 2016 2017 2018

Reykjavík Geothermal has agreed with Ethiopian ministries and agreed to PPA with EEPCo that Reykjavík Geothermal develops maximum of 1,000 MW in the next 8-10 years.Using GRMF fund, GSE is conducting a study.

20 Aluto-1 (Aluto-Langano)

75 MW 2018 The Government of Japan and World Bank has assisted in drilling of wells.

21 Tendaho-1 (Dubti)

10 MW 2018 AFD assists in well drilling for 10 MW.

Total 610 MW

MP S.No.: Site numbering in this MP study, AFD: French Development Agency Source: JICA Project Team

2.3.3 Target of the Geothermal Power Development

Target of the geothermal power development is set based on the EEPCo master plan since it

formulates the power generation plan comprehensively taking into consideration economics by plant

type. However, the EEPCo master plan did not include those currently under construction and

committed geothermal power plants; therefore, incorporating the latest information on the donor

involvements in this master plan study, the targets of each term are established as shown in Figure

2.3.3. According to the said figure, the target is set at 700 MW up to 2018, 1,200 MW up to 2025 and

5,000 MW up to 2037. Furthermore, based on geothermal potential derived from the various

geological surveys in this study, the JICA Project Team will compare the economics of geothermal to

that of other candidate plants, and will propose the development order including other plant types.



2-33

April 2015

Year Short term

up to 2018 Medium term

up to 2025 Long term up to 2037


610 1,200 5,000

Source: EEP, GSE (arranged by the JICA Project Team)

Figure 2.3.3 Targeted Installed Capacity of Geothermal Power Plant

2.3.4 Superiority of Geothermal Power Generation

As mentioned in Section 2.2.4, the EEPCo master plan forecasts the electricity sales and peak demand

which greatly increase to 221,594 GWh and 25,761 MW, respectively, up to 2037 in the reference case.

Hydropower plants that will produce around 8,000 MW has been committed and under construction at

present, and will have the largest proportion in power development in the future. Meanwhile, even if all

geothermal resources with a total potential of 5,000 MW is developed in Ethiopia, it can only meet

around 25% of the entire energy requirement. As such, geothermal energy should be prioritized as the

base-load power for the following reasons:

(1) Energy Security

Geothermal is valuable pure-domestic energy as well as hydropower, and is very effective in terms of

energy security. By developing geothermal resources, it is possible to reduce the amount of fossil fuel

which is planned to be used for thermal power plants in the future.

(2) Energy Mix

At present, neither the Government of Ethiopia nor EEP have clear targets of energy mix. Electrical

supply will overly depend on hydropower generation from the present into the future (see Figure 2.3.4).

5 200

300500

700900

1200

1600

21002300

2500

2800

3100

3400

3700

4200

4600

5000

25 130330

610

0

1000

2000

3000

4000

5000

2014

2015

2016

2017

2018

2019

2020

2021

2022

2023

2024

2025

2026

2027

2028

2029

2030

2031

2032

2033

2034

2035

2036

2037

Proposed Installed Capacity of Geothermal Power Plant Committed Plant

Inst

alle

d C

apac

ity

(MW

)



2-34

April 2015

Geothermal, which will be next largest electrical source, is expected to be developed as much as

possible in order to improve the energy mix and mitigate risk in drought mentioned below.


Figure 2.3.4 Composition of Electrical Supply in EEPCo Master Plan

(3) Reliable Electrical Supply

Geothermal, which is not affected by climate change and weather condition, is extremely reliable energy,

that its load factor is as high as 80-90% worldwide. On the other hand, hydropower is exposed to large

drop of its available generation capacity in drought period as mentioned below. And wind and solar

power generation cannot be applied as base-load because their power generation is not stable due to

climate and weather condition. Moreover, in general, because wind farm needs same size of storage

battery or thermal power plant for back-up, its initial cost is expected to be double and more. Therefore,

geothermal, which is reliable and not affected by external condition, should be developed for base-load

in Ethiopia where a sufficient quantities of electricity is not supplied.

Source: JICA Project Team, based on demand curve provided by EEP

Figure 2.3.5 Schematic Image of Electrical Supply Composition against Electricity Demand in a day

90.6%

0.3%

3.8% 5.2%2012

Hydropower

Geothermal

Wind Thermal

Hydropower

Geothermal

Wind

81.3%

6.0%

5.7%

1.4%2.9%

2.6%

2025

Hydropower

Geothermal

WindThermal

SolarBiomass

60.4%16.8%

5.0%

1.0%

2.0% 14.8%

2037

HydropowerGeothermal

Wind

Thermal

Solar

Biomass

Total Capacity: 2,141 MW 10,630 MW 21,297 MW 30,248 MW



2-35

April 2015

(4) Mitigation of the Risk of Hydropower in Drought Season

Hydropower is exposed to large depression of power generation in drought period, and available

generation capacity of hydropower plant in Ethiopia is assumed to decrease up to 80% of installed

capacity when drought occurs. The EEPCo master plan analyzed hydrological data for the past 45 years

and formulated the generation plan. However, it is concerned that larger scale of drought than the past

occurs with climate change in the future. To mitigate risk of hydropower, geothermal should be

developed as reliable base-load plants.

(5) Reduction of Cost for Diesel Power Plants/Surplus Fossil Fuel Export

As mentioned above, diesel power plant mainly belonging to the CSC has been operated, and thermal

power plants such as gas turbine, combined cycle gas turbine (CCGT), and diesel power plants are

proposed to be installed from 2018 in EEPCo master plan. By developing geothermal which can replace

fuel and is pure-domestic energy, it is possible not only to save the high cost of diesel power generation

but to reduce the usage of fossil fuel and export the surplus fuel to other countries.

(6) Greenhouse Gas Mitigation

As shown in Figure 2.3.6, geothermal power generation emits less amount of CO2 among other

renewable energies and is very environmental-friendly power generation method. Therefore,

geothermal should be developed also for the reason of prevention of a global warming. Furthermore,

selling the electricity produced by geothermal to neighboring countries contributes to suppress the CO2

emission in East-Africa region.

Source: E. Imamura and K. Nagano, Central Research Institute of Electric Power Industry, Japan, July 2010

Figure 2.3.6 CO2 Emission by Energy

943

738

474

38 25 20 13 110

200

400

600

800

1000

(g‐CO2/kWh)


CHAPTER 3 GEOTHERMAL POTENTIAL SURVEY

3.1 Geology

3.1.1 Tectonics

The study area belongs to the African Rift. The African Rift is

connected from Afar Triple Junction (see Figure 3.1.1) and

continues in the SW-SSW direction across the eastern African

countries of Djibouti, Eritrea, Ethiopia, Kenya, Uganda, and

Tanzania.

Generally, the valley is characterized by the geological

occurrence of active faults, active volcanoes, and hot springs,

which indicates a geothermal area. Geophysical and petrologic

data show that the lithosphere is thinning due to the intrusion of

hot mantle below the valley.

The valley is considered to be a separation boundary of the

African Plate. The eastern plate is called the Somalian Plate and

the western plate is the Nubian Plate. Both plates are

separating at a speed of 5 mm/year (Stamps et al., 2008).

3.1.2 Regional Geological Setting

The study area belongs to the central-southern part of the Main Ethiopian Rift (MER). MER has been

developed since Oligocene until Quaternary. During that period, major volcanic episodes are

recognized in Oligocene, middle Miocene, late Miocene, early-middle Pleistocene, and Holocene

(WoldeGabriel et al., 1990). The abstract is as follows:

The oldest volcanic activities are basalt and rhyolite flows exposed in and around the rift margins (e.g.,

Blue Nile gorge) during Oligocene, which formed lava plateau in the surrounding area. By middle

Miocene time, the rift was formed in some parts with containment basaltic flows. During Pliocene, a

huge pyroclastic flow covered the northern part of the study area. This characteristic pyroclastic flow

deposit is currently observed at a depth of around 2,100 m in the basin floor by geothermal well,

which indicates a minimum of 2 km of downthrown in the rift basin since its eruption (WoldeGabriel

et al., 1990, WoldeGabriel et al., 2000).

During Pleistocene, Wonji Fault Belt (WFB), which is the main spreading axis of MER, is formed at

the rift floor, and floor basalt and rhyolite are erupted along WFB. The volcanic activities are

characterized by peralcaline fissure basaltic eruptions and rhyolitic eruptions which formed volcanoes

and calderas. MER was formed as a symmetrical depression zone during this period and many lakes

appeared and disappeared due to the obstruction of volcanic deposits and/or climate change.

Source: http://people.dbq.edu/faculty /deasley/ Essays/EastAfricanRift.html

Figure 3.1.1 Distribution of the African Rift Valley

Afar Triple Junction

PROJECT AREA


3-1 April 2015


3.1.3 Regional Geological Structure

The MER was created by a complex system of NE-SW trending tensional faults, cut by a more recent

system of NNE-SSW trending faults known as Wonji Fault Belt.

The rift is connected from Afar Depression in the north, and

continues to symmetrical grabens at the center. The

continuation of the rift is distinctive near the border between

Ethiopia and Kenya, wherein small asymmetrical basins are

formed. Finally, the rift is connected to the Kenya Rift which

has a N-S direction.

The initial stage of MER formulation is closely related to the

Red Sea and the Aden Sea. During Mesozoic time,

north-central MER was bulged considering the thickness of the

Mesozoic sediments in Kella (North of Butajira) and Blue

Nile gorge.

In Oligocene, large and huge volcanic activity created lava

plateau. In early Miocene, three radial rifts might have

occurred in the plateau. After that, two rifts were spread and

downthrown to the sea, which became the Red Sea and the

Aden Sea. The other rift did not spread well and became MER.

Such kind of tectonic activity is considered to occur in the initial stage when the continent is apart, and

is caused by the rising of hot plume from the mantle (Figure 3.1.2).

Structural and stratigraphic relations of volcanic rocks along both rift escarpments of MER indicate a

two-stage rift development. The early phase started during late Oligocene-early Miocene time and was

characterized by a series of alternating and opposed half grabens. The half grabens evolved into a

symmetrical rift during the late Miocene period. The area also was characterized by active rifting

during Plio-Pleistocene, wherein around 2,000 m of subsidence was estimated (WoldeGabriel et al.,

1990).

Nowadays, the rift floor is covered by lakes, lacustrine sediments, alkali basalts from fissure eruptions,

volcanic ash deposits, and NNE-SSW faulting activities by WFB. These strata are classified as Wonji

Group in Figure 3.1.1.

(Source: http://www3.interscience.wiley. com:8100/legacy/college/levin/0470000201/chap_tutorial/ch07/chapter07-1.html)

Figure 3.1.2 Schematic Diagram for Development of the Red Sea Rift, the Aden Sea Rift, and the Failed African Rift (MER)


3-2

April 2015


Table 3.1.1 Stratigraphy of Main Ethiopian Rift (MER)

(Source: JICA Study Report, 2011)

3.2 Collection of Existing Information

3.2.1 Objective

All the existing geological papers, articles, and reports were collected for each geothermal site as the

background information for this Project. This information was reviewed based on the stage of

geothermal development as follows:

3.2.2 Regional Reports

Some basic and comprehensive geological investigations were carried out from the early 70s to 80s for

the purpose of exploring natural resources and geothermal development. Comprehensive

investigations and researches were conducted by the United Nations Development Programme

(UNDP) in 1973, the Ministry of Mines in 1984, and Electroconsul/Geothermica in 1987, and most of

the prospective geothermal areas were determined. Furthermore, these investigations summarized that

Aluto and Tendaho sites have the highest potential of all the prospective geothermal sites in Ethiopia.

Age(Ma)

WoldeGabriel et al.(1990) EWTEC (2008) Halcrow (2008)

Holocene0.0117

2.58

5.33 Butajira Ignimbrites

Guraghe Basalts

Shebele Trachytes

Neog

ene

Paleo

gene

Period/EpochQu

atern

ary

Pleistcene

Nazareth GroupPliocene

Miocene

23.03

Oligocene

33.9

Kella Basalts

Wonji Group

Chilalo Trachytes

Nazret Group/Afar Group

"Ancher Basalts", "ArbaGuracha Silicics"

A laji Formation

"Ancher Basalts", "ArbaGuracha Silicics"

Wonji Group

Chilalo Trachytes

Wonji Group


3-3

April 2015


3.2.3 Detailed Geothermal Survey

Detailed surveys have been conducted since the 1980s at most of the sites. These surveys consisted of

detailed geological survey (incl. geological mapping), geochemical survey/analysis, and geophysical

prospecting (MT/TEM survey). The status of surveys at each site is shown in Table 3.2.1.

Table 3.2.1 Status of Detailed Survey at Each Site

No.

Geothermal Sites Geological

Survey Geochemical

Survey Geophysical Prospecting

Other Surveys

1 Dallol ☑ ☑ -

2 Tendaho-3 (Tendaho-Allalobeda)

☑ ☑ ☑

3 Boina ☑ ☑ - 4 Damali ☑ ☑ - 5 Teo ☑ ☑ - 6 Danab ☑ ☑ - 7 Meteka ☑ ☑ - 8 Arabi - ☑ - 9 Dofan ☑ ☑ -* 10 Kone ☑ - - 11 Nazareth ☑ ☑ ☑ 12 Gedemsa ☑ ☑ -* TG well 13 Tulu Moye ☑ - - 14 Aluto-2 (Aluto-Finkilo) ☑ ☑ -* TG well 15 Aluto-3 (Aluto-Bobesa) ☑ ☑ -* 16 Abaya ☑ ☑ - 17 Fantale ☑ ☑ - Magnetic Survey 18 Boseti ☑ ☑ - 19 Corbetti ☑ ☑ ☑ 20 Aluto-1 (Aluto-Langano) ☑ ☑ ☑ 21 Tendaho-1 (Tendaho-Dubti) ☑ ☑ ☑

22 Tendaho-2 (Tendaho-Ayrobera)

☑ ☑ ☑ Radon Survey

☑: done, - : not done, -*: to be done, TG Well: Thermal Gradient well Note: The sites having limited data, are also classified as “done”. Source: JICA Project Team

It was confirmed that at least the detailed geological survey and geochemical survey were done at each

site. However, the quality and quantity of the results are not unified, e.g., entire site was not covered,

location of geological manifestations was not shown, or location of sampling was not shown.

3.2.4 Feasibility Study

Feasibility (or pre-feasibility) study was conducted at Tendaho-1 (Tendaho-Dubti), Tendaho-2

(Tendaho-Ayrobera), and Aluto-1 (Aluto-Langano) geothermal sites. In 1986,

Electroconsul/Geothermica conducted geothermal reservoir evaluation, design of facilities, and

economical evaluation, by drilling nine wells at Aluto-Langano. In 1996, the Ethiopian Institute of

Geological Survey (former GSE)/Aquater conducted geothermal reservoir evaluation by drilling three

wells at Tendaho-1 (Tendaho-Dubti) and Tendaho-2 (Tendaho-Ayrobera). Afterward, GSE continued

the drilling of three wells by themselves from 1995 to 1998.


3-4

April 2015


3.2.5 Geothermal Plant Construction /Operation and Maintenance

The first geothermal power plant was constructed at Aluto-1 (Aluto-Langano) in 1992, based on the

above feasibility study. Some reports were issued for operation and maintenance of geothermal wells

after the power plant construction.

3.3 Satellite Data Analysis

3.3.1 Objectives

Prior to the field survey, alteration zoning, mineral and lithological mapping, topographic

interpretation, and geological structure analysis were carried out using satellite images for the purpose

of obtaining data of the geothermal potential in the study area. Field survey was conducted based on

the results of the satellite data analysis and review of existing reports.

3.3.2 Methodology

For the remote sensing data, Japanese satellite products, namely, ASTER L3A and PALSAR L1.5, were

used. ASTER is an optical sensor which has visible and near infrared (VNIR) bands, short wavelength

infrared (SWIR) bands, and thermal infrared (TIR) bands as multi bands sensor (14 bands) and high

resolution (15-30 m). PALSAR is an active microwave sensor, which is not affected by weather

conditions and operable during both daytime and nighttime and has L band of multi polarization and

high resolution (15-30 m). ENVI (Ver. 5.0) software of ESRI, USA was mainly used for the processing

and analysis of satellite data.

In ASTER data analysis, the band composite image and the band ratio image are created by using SWIR

bands and the apparent distributions of various alteration zones are detected. Rock facies and mineral

mapping and interpretation of geological structures are conducted. In PALSAR data analysis, the mosaic

image of geothermal development sites is created and extraction of geological structures of lineament is

conducted.

In the analysis of ASTER image, vegetation, water, cloud, and shadow of cloud areas where data

analysis is impossible are masked. Then, the band composite images, displaying band 4 as red color,

band 6 as green color, and band 8 as blue color, are created. After calculating the band ratios between

bands, the band ratio images, displaying band 4/band 6 as red color, band 5/band 6 as green color, and

band 5/band 8 as blue color, are created. By analyzing these images, extraction of the apparent

distribution of various alteration zones, rock facies and mineral mapping, and geological structure

analysis are conducted. In the band composite image (RGB=B4, B6, B8), advanced argillic alteration

including alunite and kaolinite mainly shows peachy color; phyllic alteration including sericite mainly

shows yellowish color; and propylitic alteration including chlorite and epidote mainly shows greenish

color. In the band ratio image (RGB=B4/B6, B5/B6, B5/B8), advanced argillic alteration shows reddish

color and propylitic alteration shows purplish red color ~ deep bluish color.


3-5

April 2015


As mentioned above, using ASTER data makes it easy to identify the distribution of various

hydrothermal alteration zones. However, whether these zones include apparent distribution has to be

considered.

PALSAR data, which are synthetic aperture radar data, are useful to grasp topography and ground

surface condition. In PALSAR data analysis, the mosaic images are created by using ortho-corrected

level 1.5 products of HH single polarized wave. From these images, lineament, fault cliff, crater, caldera,

lava dome, and lava flows are extracted. In PALSAR image, outcrops of mountain range show texture of

topography with sharp edge. In and around survey areas, it is interpreted that the topography and

geological structure have NNE-SSW direction, which is clearly the same as the East African Rift, as

great geological structure. The secondary sediment areas are classified by tone according to sediment

type (difference of roughness) and texture. It is inferred that the diameter of gravel is small and

roughness is small in dark colored areas. On the contrary, in bright areas, the diameter of gravel and

roughness are large. Although the secondary sediment areas which show large roughness have the same

tone as the outcrops of mountain range, it is possible to distinguish them by texture.

3.3.3 Results

In the analysis of the ASTER data, the band composite images, which have band 4 as red color, band 6 as

green color, and band 8 as blue color, and the band ratio images, which have band 4/band 6 as red color,

band 5/band 6 as green color, and band 5/band 8 as blue color, were created. The band ratio images of

several areas are shown in the Attachment 2.1 to 2.5..

In the analysis of the PALSAR data, PALSAR mosaic images were created from HH single polarized

wave data and are shown in the Attachment 2.6 to 2.10.

The integrated analysis of GIS, where the results of ASTER DEM data were compiled as well as the

results of the ASTER and PALSAR data analysis, was conducted. As a result, the outcrop distributions

of altered rocks were extracted and geological structures were interpreted. The results will be reflected

in the next field survey as reference. The results of each site are as follows:

(1) From Dallol Site to Boina Site

In one area in the northwest region and three areas in the southeast region of Dallol site, the distributions

of hydrothermal alteration are shown and aligned in the NW-SE direction. There are lots of volcanic

topographies and circle structures lining toward the NW-SE direction. In the central region of Boina site,

small hydrothermal alteration is shown northwest of the caldera. There is a zonal distribution of volcanic

topographies and circle structures in the NW-SE direction at the western side of the caldera.

(2) Arabi Site

In Arabi site, there is zonal distribution of a lot of small volcanic topographies and circle structures in

the EW direction, accompanied by several small hydrothermal alterations in various places.


3-6

April 2015


(3) Northern Sites (Tendaho Site ~ Meteka Site)

In and around Tendaho-3 (Tendaho-Allalobeda) site, there are no obvious hydrothermal alterations.

Many lineaments in the NW-SE direction are in the southwest side. In and around Dubti site, there are no

obvious hydrothermal alterations. As unconsolidated sediments largely cover the ground surface, there

is no lineament. In and around Tendaho-2 (Tendaho-Avrobeda) site, there are a lot of parallel lineaments

in the NW-SE direction clearly in the western side of the site. A line of volcanic topographies and circle

structures in the NW-SE direction is in the northern side of the site and the distribution of hydrothermal

alteration is shown in the central part of the site. In the central part of Meteka site, several small

distributions of hydrothermal alteration are on the mountain body. From the central part to the southern

side, there are comparatively large circle structures. In the northern side, there are some small circle

structures and volcanic topographies. The distribution of hydrothermal alteration is shown in the

western side of the mountain body.

(4) Central Sites (Dofan Site ~ Tulu Moye Site)

In the central part of Boseti site, small circle structures and volcanic topographies are in the center of the

mountain body. Toward the southwest direction, there is a line of some circle structures. Around the end

of that line, volcanic structures are largely distributed. The small distributions of hydrothermal alteration

are at the western end and northeastern end of the mountain body. At the eastern end of the site, there is

a zonal distribution of volcanic topographies in the NE-SW direction. There are lots of lineaments in the

NE-SW and NNE-SSW directions. From the central part and to the western part of Gedemsa site, there

is a large circle structure. Inside the large circle structure, there are some small circle structures and

volcanic topographies which overlap with the distributions of hydrothermal alteration. There are many

lineaments in the NNE-SSW direction outside of the large circle structure. Especially, there are clear

lineaments at the eastern end of the large circle structure.

(5) Southern Sites (Aluto Site ~ Abaya Site)

In Aluto-1 (Aluto-Langano) site, there is no distribution of hydrothermal alteration. There are some

circle structures at the northeast and southwest ends of the site. No lineament is in the site. In Aluto-2

(Aluto-Finkilo) site, one small distribution of hydrothermal alteration is in the central part of the site. No

lineament is in the site. In Aluto-3 (Aluto-Bobesa) site, there is no distribution of hydrothermal

alteration. In the western part, outside the site, there are circle structures and volcanic topographies.

There is no lineament in the site and many lineaments in the NE-SW direction are in the west, outside

the site.


3-7

April 2015


3.4 Results of the Field Survey and Laboratory Analysis

3.4.1 Geological Survey

(1) Objectives

This site reconnaissance was conducted for the following purposes:

i) Confirmation of geology (Topography, rocks, structures, and alteration zones: supplemental

survey for existing site survey result);

ii) Confirmation of alteration zones which were determined by remote sensing; and

iii) Taking samples for rocks and alteration minerals.

(2) Methodology

(i) Site Survey The site reconnaissance was conducted in two stages, which are called the second and third site

reconnaissance in the study. Detailed survey points were selected based on the existing data,

results of remote sensing, and hearing from local residents. In the third site reconnaissance, the

Dallol and Arabi areas were investigated on April 30, 2014 by GSE experts only for security

reasons. The sites of the second and third site reconnaissance were as shown in Table 3.4.1.

Table 3.4.1 Schedule of Site Survey

Period Target Site Remarks

From: 17th Jan 2014 To: 1st Feb 2014 (Second site reconnaissance)

- Aluto-1 (Aluto-Langano) - Aluto-2 (Finkilo) - Aluto-3 (Bobessa) - Gedemsa - Nazreth (Boku, Sodore) - Boseti - Kone

The survey was jointly conducted by GSE and the JICA Project Team

From: 4th Apr 2014 To: 17th Apr. 2014 (Third site reconnaissance)

- Dofan - Meteka - Tendaho-1 (Dubti) - Tendaho-2 (Ayrobera) - Tendaho-3 (Allalobeda) - Seha, Lake Loma (Tendaho) - Boseti (Supplemental)

The survey was jointly conducted by GSE and the JICA Project Team

From: 1st May 2014 To: 18th May 2014 (Third site reconnaissance)

- Dallol - Arabi

The survey was conducted by GSE


(ii) Geological Analysis The samples taken during site reconnaissance were analyzed by x-ray fluorescence (XRF) for

determining rock composition and by x-ray diffraction (XRD) for determining alteration

minerals.


3-8

April 2015


Table 3.4.2 Methodology of Geological Analysis

Type of Samples Analysis Method Objective

Rock Samples XRF Composition of Rock (%) (SiO2, Al2O3, CaO, MgO, Na2O, K2O, Cr2O3, TiO2, MnO, P2O5, SrO, BaO)

Alteration Minerals

Zeolite and Others

XRD (powder specimen)

Determination of alteration mineral

Clay Minerals

XRD (oriented specimen)

Determination of clay mineral

- Treated by Ethylene Glycol

- Treated by HCl

Identification of clay minerals (Chlorite- Kaolinite, Chlorite- Smectite)


(3) Results

The results of the geological survey are as follows:

(i) Site Survey Results The second and third site reconnaissances have been conducted The results of the site reconnaissance

are summarized by the following items as shown in Table 3.4.3.

i) Topography and route map

ii) General geology

iii) Geological structure, fault, and others

iv) Geothermal manifestation

v) Alteration

vi) Photos and others


3-9

April 2015


Table 3.4.3 Example of Site Reconnaissance Sheet

Site No. 2 Site Name: Tendaho-3 (Tendaho-Allalobeda) Regional State: Afar Satellite Imagery and Route Map

Legend Surveyed Route

Fumarole

Hot Spring

Other Geological Feature

Center Coord. (WGS84) Lat: N 11038’34.29” Lon: E41000’58.70” Surveyed Date: 12 April, 2014 by Google Earth Pro: http://www.google.com/earth

General Geology The site is located at the western edge of Manda- Hallaro Graven. Layered basalt and andesite lava of Afar Stratoid are observed (1-4Ma, by V. Accolela et.al. (2008))

Photos

Overview

Geological Structure, Fault and Others The site is located along NW-SE marginal fault of Manda- Halaro Graven, associated with minor faults. The height of fault scarp is approx. 200m.

Manifestation More than 20 hot springs and geysers are found along NW-SE marginal fault within 1 km diameter, showing definite relationship between the faults and manifestations. Whitish gray amorphous silica is deposited around the springs.

Geyser

Alteration No alteration was observed at the host rock.

Others Remote sensing result shows no indication of alteration; due to no alteration minerals were found.

0.5 km N


3-10

April 2015

http://www.google.com/earth

http://www.google.com/earth


(ii) Results of Laboratory Analysis (XRF and XRD) The results of the geological laboratory analysis (XRF and XRD) are shown in Table 3.4.4. The results

are as follows:

Result of XRF Analysis for Rock Composition

SiO2-K2O+Na2O Diagram (TAS Diagram)

SiO2-K2O+Na2O Diagram is commonly used for classifying rock series and type. Figure 3.4.1

shows the results of analysis for the project with the results of existing reports

(Electroconsult/Geotermica, 1987; UNDP, 1973).


Figure 3.4.1 SiO2-K2O+Na2O Diagram (TAS Diagram)

The results are as follows:

Analyzed data were concordant with

the data in existing reports and showed

alkali rock series.

Figure 3.4.2 shows the same diagram

for Olkaria Geothermal Field in Kenya.

The composition of trachyte and

ryolite is similar to that of Olkaria. It is

considered that most of the target sites

in Ethiopia are geologically promising site

in the entire African Rift.

Source: J.K.Regat (2004)

Figure 3.4.2 SiO2-K2O+Na2O Diagram in Olkaria Geothermal Field in Kenya


3-11

April 2015


FeO-MgO-K2O+Na2O Diagram

FeO-MgO-K2O+Na2O Diagram is commonly used for the trend of magmatic segregation in rock

series. Figure 3.4.3 shows the results of analysis for the project with the results of existing

reports.


Figure 3.4.3 FeO-MgO-K2O+Na2O Diagram

Analyzed data were concordant with the data in existing reports and almost all the samples

showed similar trends to that of tholeiitic series. It is considered that all the sites may have similar

characteristics such as depth of magma chamber, cooling velocity, and so on.


3-12 April 2015

The Project for Formulating M

aster Plan

on D

evelopment of G

eothermal Energy in Ethiopia

Final Report

Table 3.4.4 XRF Analysis Results


Nippon Koei C

o., Ltd. JM

C G

eothermal Engineering C

o., Ltd Sum

iko Resources Exploration & D

evelopment C

o., Ltd.

3-13

April 2015


(iii) Result of XRD Analysis for Alteration Minerals Table 3.4.5 shows the results of determination of minerals by XRD.

Table 3.4.5 Mineral Occurrence by XRD


According to the results of site reconnaissance, rock alteration was observed only around

geothermal manifestations. It was not observed in wider areas such as alteration zone, except for

Dofan and Meteka sites.

The above results shows that low-grade alteration has occurred in many sites, and is characterized

by the occurrence of Quartz, Opal-A, Opal-CT, Clinoptilorite, Halloysite, Smectite, which is

concordant with the site reconnaissance. The occurrence of kaolinite at Gedemsa and Finkilo sites

shows trace of hydrothermal alteration.

No. Site Location Sample Quartz Opal - CT Opal - A Clinoptilolite Kaolinite Halloysite Smectite

140119-02 Bobesa (Aluto-2) Bobessa Altered Clay △ ＋

140120-03A Bobesa Bobessa Altered Obsidian ＋－ 140120-03B Bobesa Bobessa Zeolite ＋－ 140120-04 Bobesa Bobessa Altered Rock －＋ 140120-05 Bobesa Bobessa Secondary Mineral ＋ 140120-06 Bobesa Gebiba Clay Mineral ＋ 140121-03 Finkilo (Aluto-3) Finkilo Yellow Tuff －－ 140122-02 Finkilo Adoshe Yellow Clay ＋＋ 140122-03 Finkilo Adoshe Red Clay －－ 140122-04 Finkilo Adoshe White Mineral ○ － 140122-05 Finkilo Humo Clay －＋＋ 140122-06 Finkilo Humo White Mineral ＋ 140122-07 Finkilo Shutie Clay △ ＋ 140122-08 Finkilo Shutie White Mineral △ － 140125-01 Gedemsa Sambo Zeolite Vein －＋＋ 140125-03 Gedemsa Sambo Altered Welded Tuff ○ 140125-04 Gedemsa Sambo White Mineral ○ ＋＋ 140126-01 Nazereth Boko Yellow Tuff △ ○ 140131-03 Boseti Kintano Altered Andesite －－ 140131-04 Boseti Kintano White Mineral ＋＋


3-14

April 2015


3.4.2 Geochemistry

(1) Objectives

The main objective of geochemical study is to characterize the geothermal reservoirs using geochemical

properties of fluid and gas collected from geothermal manifestations (hot springs and fumaroles). For

this reason, the study includes site reconnaissance of geothermal manifestations, measurement of the

location, temperatures, and other properties, and sampling of fluid and gas. The reservoir temperature

and origin of geothermal fluid and gas are interpreted based on the geochemical properties (chemical

and isotopic compositions) of the fluid and gas samples.

Some collected samples are analyzed by the JICA study team in Japan, and also by GSE at the GSE

laboratory. The analytical results are used to verify the analytical precision of GSE by comparing the

results of GSE and the JICA study team.

(2) Methodology

(i) Site reconnaissance Site reconnaissance was carried out in the second and third site reconnaissance survey. Because of

a security reason, Dallol, Arabi, and Erer areas were surveyed by only GSE members. The survey

areas are as follows:

The second site reconnaissance: Aluto, Bobesa, Finkilo, Gedemsa, Nazreth, Boseti, and Kone

The third site reconnaissance: Dofan, Meteka, Dubti (Tendaho-1), Ayrobeda (Tendaho-2),

Allalobeda (Tendaho-3), Seha, Lake Loma, Boseti (additional

survey), Dallol, Arabi, and Erer

The following operations were conducted on site.

1. Measurement of coordinate and altitude of geothermal manifestations (by using a portable

GPS navigator)

2. Observation of geothermal manifestations

3. On-site measurement of temperature, pH, and conductivity of geothermal manifestations,

river and lake water

4. Sampling of hot spring water, fumarolic gas, water and steam from geothermal wells, and

river/lake water.

The results of the site reconnaissance are summarized in Table 3.4.6 (the southwestern part of the

rift valley), and Table 3.4.7 (the northeastern part). The total survey locations are 71 points, from

which 41 samples (32 water and 11 gas samples) were collected.


3-15

April 2015


aster Plan

on D

evelopment of G


Final Report


Table 3.4.6 Summary of the site reconnaissance in the southwestern part of the Ethiopian Rift Valley

Nippon Koei C

o., Ltd. JM

C G


o., Ltd Sum


evelopment C

o., Ltd.

3-16

April 2015


aster Plan

on D

evelopment of G


Final Report


Table 3.4.7 Summary of the site reconnaissance in the northeastern part of the Ethiopian Rift Valley

Nippon Koei C

o., Ltd. JM

C G


o., Ltd Sum


evelopment C

o., Ltd.

3-17

April 2015


(ii) Sampling i) Hot spring water, water from geothermal wells, and river/lake water

Hot springs measuring the highest temperature and flow rate in the site were preferentially sampled.

At Shenemaya (Gedemsa) and Welenchiti (Boseti), water wells were sampled as a hot spring

because they showed higher temperature than the ground temperature. LA-6 and LA-8, which are

geothermal wells in the Aluto area, were also sampled as a representative of reservoir fluid.

Water sample was once put in a jug, and then transferred into polyethylene bottles that can be

tightly capped. Before the sampling, the jog and bottles were rinsed three times or more with

sample water. Sample water was divided into several bottles depending on the analytical

components and methods. The samples were pretreated with a proper amount of HCl (1:1) solution

for analysis of metal, ammonia, and silica, with cadmium acetate (5%) solution for hydrogen

sulfide, and with potassium hydroxide for carbon dioxide, respectively.

ii) Fumarolic gas and steam from a geothermal well

Fumaroles measuring the highest temperature and flow rate in the site were preferentially sampled.

At the Aluto area, steam from well LA-8 was sampled as a representative of reservoir steam

containing geothermal gas.

In the sampling for fumaroles, a funnel was put over a fumarole vent, and then sealed on its rim

with soil or mud to prevent air contamination during the sampling. After that, a rubber tube was

connected to the funnel in order to extract gas. As to a geothermal production well LA-8, a

sampling separator was connected to a sampling valve on the two-phase line, then a rubber tube

was connected to a nozzle of steam sampling valve on the separator. A sampling apparatus called

gas burette that was filled with an alkaline solution was connected to the rubber tube to introduce

the gas or steam into the gas burette. In the gas burette, CO2 and H2S were dissolved in the alkaline

solution, and residual gas (R gas) accumulated at the head of the gas burette. After collecting a

sample, R gas was transferred from the gas burette to a gas collector (a glassware), and then, the

alkaline solution was washed out into a measuring flask, and diluted to 250 ml with distilled water.

The diluted alkaline solution was divided into two polyethylene bottles dedicated to analysis of

CO2 and H2S, respectively. A cadmium acetate (5%) solution was added into the samples for H2S

analysis on site.

(iii) Analysis of samples Table 3.4.8 and Table 3.4.9 show analytical components and analytical methods, respectively.


3-18

April 2015


Table 3.4.8 Analytical components


Table 3.4.9 Analytical methods


(3) Results

(i) Profile of geothermal manifestations in the Ethiopian Rift ValleyLocation (coordinate), altitude, and temperature of survey points are summarized in Tables 3.4.6

and 3.4.7, and the distribution of temperature of geothermal manifestations is shown in Figure

3.4.4.

In the southwestern part of the Ethiopian Rift Valley, a main geothermal manifestation is fumarole

located in uplands. Fumaroles whose temperature is more than 90°C are located in Aluto, Bobesa,

and Gebiba; only the fumaroles in Gebiba show a boiling temperature in the southwestern part.

The other fumaroles are of lower temperatures (70-90°C) less than a boiling temperature. The low

temperature suggests that steam generated at a depth is cooled during its ascending to the surface


3-19 April 2015


by surrounding rock. In this cooling process, a part of the steam condensates into liquid (water),

resulting in a change of chemical composition from the original one controlled by the reservoir

temperature. Gas geochemical thermometers thus cannot be applied to the low-temperature

fumarolic gases.


Figure 3.4.4 Distribution of geothermal manifestations in the Ethiopian Rift Valley


3-20

April 2015


Hot springs are distributed mainly in lowlands around Langano Lake and the Nazareth area. Their

temperatures are middle to low, ranging from 65° to 35°C, and boiling spring cannot be found.

Relatively high temperatures are 65°C of Ouitu (Langano lake) and 50°C of Sodere (Nazareth).

In the northeastern part of the Ethiopian Rift Valley, fumaroles and hot springs are distributed in

upland and lowland areas. The manifestations show temperatures higher than those in the

southwestern part. Fumaroles with temperatures higher than 90°C are located in Dofan, Dubti,

Ayrobeda. In Dubti and Ayrobeda, temperatures of fumaroles are slightly higher than a boiling

temperature. Hot springs distribute in Dofan, Meteka, Allalobeda, Seha; there are hot springs with

the temperature higher than 80°C, except for Dofan. A boiling hot spring is located at Allalobeda.

Taking a wide view of the Ethiopian Rift Valley, Aluto-Langano and Tendaho (Allalobeda,

Ayrobeda, Dubti, Seha) are the remarkable sites showing prominent activity of geothermal

manifestations.

(ii) Results of analysis of samples The analysis results of chemical and isotopic compositions are shown in Table 3.4.10 for water

and Table 3.4.11 for gas. Geochemical characteristics of geothermal water and gas are examined

with those results and reference data. The reference data are taken from Aquater (1980, 1991),

ELC/Geotermica (1987), Gonfiantini et al. (1973), UNDP (1973, 1976, 1977), Panichi (1995),

D'Amore et al, (1997). For description of the locations of sampling points, the survey areas are

divided into four major regions; they are, along a direction from southwest to northeast in the rift

valley, [1] Lake District (Abaya to Wonji), [2] Southern Afar (Fantale to Meteka), [3] Northern

Afar (Teo/Danab to Tendaho), and [4] Danakil Depression (Dallol).

(iii) Origin of geothermal fluid Origin of geothermal fluid (water from geothermal wells and hot springs) is examined using the

relationship between δD and δ18O. As shown in Figure 3.4.5, waters from the geothermal

manifestation, rivers, and lakes are plotted close to the meteoric water line, which means that

meteoric water is the origin of the geothermal waters. Much higher isotopic values in both oxygen

and hydrogen are seen in Figure 3.4.5, indicating isotopic mass fractionation caused by intense

evaporation (see the evaporation line in the figure) in the rift valley as mentioned by Panichi

(1995).


3-21

April 2015


aster Plan

on D

evelopment of G


Final Report


Table 3.4.10 Results of chemical and isotopic analysis for water samples

Nippon Koei C

o., Ltd. JM

C G


o., Ltd Sum


evelopment C

o., Ltd.

3-22

April 2015


aster Plan

on D

evelopment of G


Final Report


Table 3.4.11 Results of chemical and isotopic analysis for gas samples

Nippon Koei C

o., Ltd. JM

C G


o., Ltd Sum


evelopment C

o., Ltd.

3-23

April 2015



Figure 3.4.5 Relationship between δD and δ18O of geothermal and surface waters

(iv) Characteristics of main anions in geothermal water Relative concentrations of main anions (Cl, SO4, HCO3) are shown in Figure 3.4.6 (based on

Giggenbach, 1991). This figure illustrates that the anion composition of waters from geothermal

wells and hot springs differs by the sample locations; the geothermal waters in Lake District and

Southern Afar are rich in HCO3, on the contrary, the geothermal waters in Northern Afar are rich

in Cl. The Cl-rich waters in Northern Afar are similar to those from geothermal systems

developed in subduction zones (see mature waters in the figure). Water samples of Meteka and

Arabi show intermediate relative concentration of HCO3 and Cl. Dallol in Danakil Depression

has extremely high concentration of Cl and extremely low pH (Cl 197000 mg/l, pH < 1 in Table

3.4.10). This suggested that the chemistry of Dallol hot spring is strongly affected by volcanic

HCl gas.

In Lake District, waters are rich in HCO3 among surface water (river and lake), hot spring, and

geothermal well discharges. This observation indicates that the anion composition of the surface

water is unchangeable in the geothermal reservoir where the surface water penetrates.

Giggenbach (1991) states that HCO3-rich waters are found at margins of a thermal area in the

geothermal systems developed close to the subduction zones. The observation in Lake District,

however, indicates that HCO3-rich water can be reservoir water in the southwestern part of the

Ethiopian Rift Valley.

Looking at Figure 3.4.6(b) closely, geothermal wells in Aluto and hot springs in its neighboring

area, Langano, together show very similar anion composition. This similarity demonstrates that

the geothermal fluids from Aluto and Langano are originated in a single geothermal system. This

point of view is used to estimate reservoir temperature as mentioned later.


3-24

April 2015



Figure 3.4.6 Relative Cl, SO4, and HCO3 contents of geothermal and surface waters on weight basis

In Tendaho, Northern Afar, unlike Aluto-Langano, geothermal waters and river waters are quite

different in anion composition, which could be caused by the different condition in water-rock

interaction. As can be seen in Figure 3.4.5, geothermal waters in Tendaho demonstrate the oxygen

shift with which geothermal water becomes rich in heavy oxygen isotope compared to surface

(recharge) water as a result of water-rock interaction. Those observations of the anion and

isotopic composition in Northern Afar and Aluto-Langano indicate that the water-rock interaction

is probably progressed more in Northern Afar.

(v) Estimation of reservoir temperature based on geochemical thermometers In order to estimate the progress of water-rock interaction, Na-K-Mg diagram (Giggenbach,

1988) is drawn in Figure 3.4.7. This figure implies that waters from geothermal wells in Tendaho

and hot springs in Allalobeda is fully equilibrated with surrounding rock, which is consistent with

the fact that the geothermal waters are rich in Cl and affected by oxygen shift in the isotopic

composition. On the contrary, waters from geothermal wells in Aluto and hot springs of Oiutu in

Langano are partially equilibrated with surrounding rock and the other hot spring waters are

immature in the state of water-rock interaction. In some cases, geochemical thermometers using

Na and K are unreliable where it is applied to the waters that are not fully equilibrated with the

reservoir rock (Giggenbach, 1991). Reservoir temperature, therefore, can be examined by

comparison among several geochemical thermometers including quartz thermometer in this study.


3-25

April 2015



Figure 3.4.7 Relative Na, K, and Mg contents of geothermal waters

Table 3.4.12 summarizes the results of calculation of geochemical thermometers using the

chemical compositions obtained in this work. These results are compared with geochemical

temperatures calculated for the reference chemical data, and temperatures obtained in well

loggings (Seifu, 2006; D'Amore et al., 1997) as shown in Figures 3.4.8 and 3.4.9. These figures

provide observations as follows: [1] the quartz thermometer shows a good agreement with

well-logging temperatures of geothermal wells (LA-6, LA-8, TD-1, TD-2, TD-4), [2]

temperatures calculated with the quartz thermometer converge within a narrow range in each

survey site, so that the quartz temperatures can be recognized as a representative one of the hot

spring aquifer. In contrast, the calculation results using Na-K and Na-K-Ca thermometers vary

widely within the each site. [3] Geochemical temperatures of hot springs, except for quartz

temperatures of Allalobeda, are lower than those of geothermal wells. [4] There is no a single

trend in the orders of temperatures between quartz and Na-K/Na-K-Ca temperatures throughout

the all survey sites.


3-26

April 2015


aster Plan

on D

evelopment of G


Final Report


Table 3.4.12 Calculated results of geochemical thermometers for geothermal waters

Nippon Koei C

o., Ltd. JM

C G


o., Ltd Sum


evelopment C

o., Ltd.

3-27

April 2015



Figure 3.4.8 Comparison of temperatures calculated with geochemical thermometers for the southwestern part of the Ethiopian Rift Valley


Figure 3.4.9 Comparison of temperatures calculated with geochemical thermometers for the northeastern part of the Ethiopian Rift Valley


3-28

April 2015


Based on the conditions above, no geochemical temperature of hot spring can directly indicate

plausible reservoir temperature. For this reason, we estimate reservoir temperature with the

assumption in which Aluto-1 (Aluto-Langano) can be treated as a single geothermal system

including a geothermal reservoir and hot spring aquifer, and conditions described above in [1] and

[2]. In the process of estimation, it is assumed that the temperature difference between the

geothermal reservoir and hot spring aquifer is represented by the deference in quartz temperature

between a geothermal well and an Oiutu hot spring. In order to estimate a reservoir temperature,

this temperature difference will be added to the quartz temperature of hot springs equally in each

site. The temperature difference was calculated to be 70°C by subtracting the quartz temperature

of the Oiutu hot spring from that of LA-8, which indicates an intermediate temperature among the

geothermal wells in Aluto. This manner follows a principle taking a uniform process to estimate

reservoir temperatures throughout the survey sites.

Gas geochemical thermometers can also be used for fumarolic gas to estimate reservoir

temperature. However, in the Ethiopian Rift Valley, gas thermometers is considered unreliable

because most of the fumaroles have temperatures less than a boiling temperature, and contain air

in a large proportion. For this reason, gas geochemical thermometers were applied to the

calculated gas chemical compositions corrected for mixing of air. As shown in Table 3.4.13, the

calculation results of gas thermometers show a wide variety of temperatures with no tendency,

which indicates that the use of gas thermometers should be avoided for estimation of the reservoir

temperature, and that geochemical thermometers using water composition is more practical for

the purpose.

Table 3.4.13 Calculated results of geochemical thermometers for geothermal gases



3-29

April 2015


The estimated reservoir temperatures, which were calculated by adding the temperature

difference (70°C) between the geothermal reservoir and hot spring aquifer to the quartz

temperatures of hot springs, are shown in Table 3.4.14. For the sites where no chemical data of

hot springs are available, the estimated reservoir temperatures are assumed to be the same as

those of a neighboring site. On the basis of this estimation of reservoir temperatures, the

temperature conditions were eventually arranged for practice of a volumetric method to assess the

geothermal potential. In this condition setting, distribution density and activity of geothermal

manifestations including fumaroles as well as hot springs are considered. The final conditions of

the reservoir temperature are expressed by the four classes of temperature ranges, as follows (see

also Figure 3.5.2): A: 240°C–290°C, B: 210°C–260°C, C: 170°C–220°C, D: 130°C–170°C.

Table 3.4.14 Estimation of ranges of reservoir temperature for a volumetric method


(vi) Relationship between the origin of geothermal gas and heat source The origin of geothermal gas can be interpreted from chemical and noble gas isotopic

compositions (Table 3.4.11) of gas samples. Figure 3.4.10 depicts He-Ar-N2 relative

concentration of gases along with the end members mentioned in Giggenbach (1966). Figure

3.4.10(a) plots analytical raw data. Gas from a geothermal well (LA-8), fumaroles having

temperatures higher than a boiling temperature (Gebiba, Ayrobeda, Dubti), and bubbling gas in a

Meteka hot spring are plotted close to a mixing line of Air-saturated water and a mantle

component. The largest mixing ratio of the mantle component is seen in the gas from LA-8, so

that the composition probably represents a gas composition in the geothermal reservoir. From


3-30

April 2015


these observations, it can be inferred that an origin of the gas is emanation gas from the mantle

beneath the rift valley. On the other hand, gas samples form fumaroles with lower temperature

(Boko, Boseti, Bobesa, and Dofan) are abundant in the air component, which could be gained by

the fumarolic gas ascending through an unsaturated layer above a water label. Figure 3.4.10(b)

uses calculated gas chemical compositions corrected for air mixing, and reveals the mantle

component signature in such low-temperature fumarolic gases from Boko and Bobesa.


Figure 3.4.10 Relative He, Ar, and N2 contents of geothermal gases

The Mantle component in geothermal gas can be confirmed by noble gas isotopic ratio as inferred

by the relationship between 3He/4He and 4He/20Ne with end members of air, crust, and mantle

(Leśniak et al, 1997) in Figure 3.4.11. In the figure, geothermal gases in the Ethiopian Rift Valley

are plotted close to the mixing line connecting the mantle and air components, which means that

the geothermal gas contains emanation gas from the mantle.

The Great Rift Valley, where the upwelling movement of mantle splits the crust underneath, is

supplied with a large quantity of heat from the mantle. The mantle component in geothermal gas,

thus, can be an indicator for the mantle or magma generated from the mantle as the heat source.

Furthermore, the movement of the gas indicates a flow path running from a depth to the surface,

that is, a fracture zone. Because supply of meteoric (ground) water into the fracture zone develops

a geothermal reservoir there, it can be said that the obvious contribution of the mantle component

in the geothermal gas on the surface indicates a highly potential geothermal reservoir at a depth.


3-31

April 2015



Figure 3.4.11 Relationship between 3He/4He and 4He/20Ne of geothermal gases

(vii) Verification of chemical analysis quality of GSE In order to verify the precision of chemical analysis at GSE, GSE and the JICA study team

analyzed shared water samples, and compared the both results. For a practical comparison of the

results, samples were selected from a wide variety of concentration of chemical components. The

selected samples were of LA-8, Oiutu #2, Oiutu #84, Shenemaya, Sodere, Gergedi (6 samples).

As shown in Figure 3.4.12, the comparison of the results between GSE and the JICA study team

are summarized as below.


3-32

April 2015



Figure 3.4.12 Comparison of analytical results between GSE and the JICA study team

Good agreement between GSE and the JICA study team can be seen in the analysis results of pH, EC (electric conductivity), Cl, SO4, HCO3, F, Na, and K, except for SO4 of LA-8, which proves sufficient analytical precision of GSE.

A large difference is found in a high concentration of SiO2. A cause for the difference might be a lack of digesting of polymerized silica in the process of analysis at the GSE laboratory. Because SiO2 concentration is frequently used in geochemical thermometers, improvement of SiO2 measurement is the highest priority for GSE.


3-33

April 2015


Although there is no large difference in K concentrations between GSE and the JICA study team, a slight deference can be found in the high concentration of LA-8. Because K is an important component used in geochemical thermometers together with Na, it is preferable for GSE to improve the analytical precision of K in high concentration.

GSE's analytical precision is insufficient for Ca and Mg. A solution to this problem is use of ICP atomic emission spectroscopy. GSE possesses an ICP spectrometer, but it is not operated. Use of this ICP spectrometer with proper maintenance would lead to a significant improvement in analysis of Ca and Mg. In addition, the ICP spectrometer can analyze many other elements, so that the spectrometer will enhance the capacity of GSE in chemical analysis.

Considering the conditions above, the top priority in the chemical analysis at the GSE laboratory is to

achieve sufficient analytical precision for a high concentration of SiO2 and K. For this reason, in the

training course for GSE in Japan, engineers were trained in SiO2 measurement with spectrophotometry,

and Na and K with flame atomic emission spectroscopy. These methods are simple and required

apparatus is relatively inexpensive, so that the employment of these methods is effective in capacity

building of the GSE laboratory.

3.5 Preliminary Reservoir Assessment

3.5.1 Objectives

The preliminary geothermal reservoir source assessment was conducted to facilitate the results to use

as basic information for formulating Master Plan on Geothermal Energy Development.

3.5.2 Definition of Resource and Reserve

For the evaluation of potential in the oil industry, the potential is classified into “resource” and

“reserve” in accordance to the project stage and economics. For geothermal projects, there are lots of

studies that try to classify “resource” and “reserve” based on a similar concept. However, no

universally recognized standards exist for classifying and reporting geothermal “resources” and

“reserves”. For this study, the geothermal resource was described according to the definition of

Australian Geothermal Energy Group Geothermal Code Committee (AGRCC) in the “Geothermal

Lexicon For Resources and Reserves Definition and Reporting Edition 2 (2010)”. This definition is the

most distinct for resource evaluation at the early stage among similar studies according to the

International Energy Agency (IEA)’s comparative study. The conceptual model of this definition is

shown in Figure 3.5.1.

The code recognizes three categories of geothermal “resources”, namely: “inferred”, “indicated”, and

“measured”, which represent three different levels of geological knowledge and probability of

occurrence. Two categories of “reserves” are recognized (“probable” and “proven”), based upon the

likelihood and reliability of the modifying factors and the type of resource. The modifying factors

depend on economic, environmental, and political context, and assess the commerciality of the


3-34

April 2015


“resources”.

Source: AGRCC, 2010

Figure 3.5.1 Relations of Geothermal Sources, and Geothermal Reserves

The Federal Democratic Republic of Ethiopia’s Scaling-Up Renewable Energy Program Ethiopia

Investment Plan (Draft Final) shows that the planning aspects of geothermal projects consist of: (i)

review of existing information on a prospect; (ii) detailed surface exploration (geology, geochemistry,

and geophysics); (iii) exploration drilling and well testing (minimum of three wells); (iv) appraisal

drilling (4-6 wells) and well testing; (v) feasibility studies; (vi) production drilling, power plant design,

environmental impact assessment, and reservoir evaluation; (vii) power station construction and

commissioning; and (viii) reservoir management and further development.

The comparison between these eight stages and AGRCC’s categories is shown in Table 3.5.1.

Table 3.5.1 Comparison between Eight Stages and AGRCC’s Categories

Eight Development Stages in Ethiopia AGRCC, 2010

Resource Reserve (i) Review of existing information on a prospect

Inferred - (ii) Detailed surface exploration (geology, geochemistry, and geophysics)

(iii) Exploration drilling and testing (minimum of three wells) Indicated Probable

(iv) Appraisal drilling and well testing (v) Feasibility studies

Measured Proven

(vi) Productive drilling, power plant design, EIA, and reservoir evaluation

(vii) Power station construction and commissioning

(viii) Reservoir management and further development


According to the above comparison, the category of the survey sites is classified. There are no boring Nippon Koei Co., Ltd. JMC Geothermal Engineering Co., Ltd Sumiko Resources Exploration & Development Co., Ltd.

3-35

April 2015


holes drilled in the geothermal reservoir in the surveyed sites except Aluto and Tendaho. Therefore,

the geothermal resources of all other sites are classified under “inferred resources”. For Aluto-1

(Aluto-Langano) and Tendaho-1(Tendaho-Dubti) sites, there are boring holes drilled already that

increased geological knowledge and confidence. Therefore, these two sites are classified as “indicated

resource” and/or “measured resource”.

3.5.3 Methodology of Reservoir Resource Assessment – Volumetric Method

The Volumetric method is used for the reservoir resource assessment. The method was introduced by

USGS (1978) for a rapid assessment. The method assumes the following conditions. 。

• Geothermal heat energy is stored or confined in a reservoir that has a finite volume under the ground;

• The outer limits of the reservoir are defined with parameters obtained by explorations. The outer limits shall be within reachable realm with current or near-future technology;

• The stored heat energy is recovered to the ambient as a form of geothermal fluid. The fluid is recharged from outside of the reservoir;

• The heat is not replenished to the reservoir from outside of the reservoir. • The reservoir resource assessment is conducted in such a way that the heat energy is

constantly recovered for the period of the plant life time; the heat energy will suddenly run out at the end of the plant life time; total recovered heat energy (kJ) is calculated and then converted to the power capacity (MW) of the power plant.

• In this regards however, recovery factor is considered in the calculation since not all the heat energy is recovered to the ambient.

The equations proposed by USGS (1978) are as follows

)( refrr TTCVq −= ρ [kJ] (1)

rWHg qqR = [ - ] (2)

)( refWHWHWH hhmq −= [kJ] or [kW] (3)

(for a geothermal reservoir temperature > 150 ºC )

[ ])( 000 ssThhmW WHWHWHA −−−= [kJ/s] or [kW] (4)

)/(FLWE uAη= [kJ/s] or [kW] (5)

qr ：heat energy of the reservoir q_WH ：heat energy at well heat Tr ：reservoir temperature Tref ：reference temperature

T0 ：rejection temperature (Kevin)

m_WH ：mass of geothermal fluid at wellhead

h_WH ：specific enthalpy of fluid at wellhead

href：specific enthalpy of fluid at reference temperature h0：specific enthalpy of fluid at rejection temperature

s_WH ：specific entropy of fluid at wellhead s0 ：specific entropy of fluid at rej ection temperate ρC ：volumetric specific heat of the reservoir V ：reservoir volume Rg ：recovery factor WA ：available energy (exergy energy) E ：plant capacity F ：plant factor（ 90% ）Ｌ：plant life time（ 30year）


3-36

April 2015


However, the USGS calculation method has appeared not to be prevailing in references, partially

because that the equation (4) includes rT dependent parameters ( WHh and WHs ) that render the

calculation with probabilistic approach complicated and that the equation (4) shall be the equation (4)’

when used with the equation (1), (2) and (3).

[ ]}{(}){( 0)00 ssThhhmW refSWHrefWHWHA −−−−= − [kJ] or [kW] (4)’

It is noted that if all the recovered heat at the wellhead is to be cast directly into a flash cycle, then

)( refWH hh − = WHh )0( =refh with the condition that the final state of the recovered geothermal fluid is

defined at the condenser of the rejection temperature (T0); since the enthalpy of water is defined as zero at the triple point, i.e. 0=refh , then refT =0.01 ºC for the equation (1), (2), (3) and (4)’.

Instead, the following equation has been used in many references.

)/()( FLTTCVRE refrcg −= ρη [kJ/s] or [kW] (6)

Where ηc is conversion factor.

Unreasonably higher temperatures such as 150 ºC or 180 ºC or others have been used as the reference

temperature, though rational reasons have appeared not to be given; the reasons on why and/or the

conversion factor is selected have appeared either to be provided. Hence, it appears not to be appropriate

to use such equation for the assessment of the reservoirs in Ethiopia.

Instead, the JICA Team herein use a rational and practical calculation method for the assessment of

reservoir with temperature not less than 180 ºC shown below. The detailed explanation of this

explanation has been provided in a paper attached as Appendix.

)()(ζ FLTTCVRE refrgex −= ρη [kJ/s] or [kW] (7)

ffrr CCC ρϕρϕρ +−= )1( [kJ/s] or [kW] (8)

Where ηex is exergy efficiency, ζ is “heat allocation function”, φ is porosity of the reservoir rock mass, ρr is density of the

reservoir rock, Cr is the specific heat of the reservoir rock, ρf is density of fluid in the void of the rock mass, and Cf is the

specific heat of the fluid in the void of the rock mass, Tref =0.01 ºC(triple point).

With the typical conditions that the separator temperature and the condenser temperature are 151.8 ºC

and 40 ºC respectively, the heat allocation function ζ is given below.

4591082158.00046543806.00000124900.00000000127.0ζ 23 −+−= rrr TTT (9)

The exergy efficiency has been calculated for the case of separator temperature = 151.8 ºC and

condenser temperature = 40 ºC based on the data of actually operating power plant all over the world.

Note that this exergy efficiency is different from that of the utilization factor of the USGS and the

conversion factor of the prevailing method.

ηex= 0.77 ± 0.05 (9)

Recovery factor is as given below.


3-37

April 2015


Rg= 0.05 – 0.20 (10)

Note that this calculation method gives similar results to the ones calculated by the USGS method, thus

the validity has been confirmed.

In addition, when reservoir temperature is estimated below 180, binary system is assumed. For this case,

the equation (5) was used with the parameters of ηc=0.05-0.08, Tref=80 ºC.

3.5.4 Probabilistic Approach － Monte-Carlo Method

As a probabilistic approach, the Monte Carlo method was used. The soft-weir was the Cristal Ball of

Oracle Company. The calculation conditions are given in the table below.

Table 3.5.2 Parameters for reservoir assessment

Parameter Symbol Unit Range Probabilistic

distribution Min. M.L Max.

Volume V m3 0 tbp tbp Triangle

Reservoir temperature Tr ºC tbp tbp tbp Triangle

Rock density ρr kg/m3 - 2600 - fixed

Rock volumetric specific heat Cr kJ/kg - 1.0 - fixed

Fluid volumetric density ρ f kg/m3 - 950 - fixed

Fluid specific heat Cf kJ/kg - 5 - fixed

Porosity Φ % 5 - 10 Uniform

Recovery factor Rg % 5 20 Uniform

Reference temperature for flash type Tref ºC - 0.02 - fixed

Rejection temperature (condenser temperature) *

T0 ºC - 40 - fixed

Separator temperature* - ºC - 151.8 - fixed

Exergy efficiency for flash ηex % 72 77 82 Triangle

Reference temperature for binary type Tref ºC - 80 - fixed

Conversion factor for binary ηc % 5 6.5 8 Triangle

Plant factor F % - 90 - fixed

Plant life L year - 30 - fixed

Min.: Minimum; Max.: Maximum, M.L.: Most likely; tbp: to be proposed; *: given in the heat allocation function


3.5.5 Proposed the parameters

There has not been much information to determine the necessary parameters for the volumetric method.

Hereunder described explanations on how the essential parameters have been proposed for future

reviews as development states should proceed.

3.5.6 Proposal of the reservoir volumes

In most of the target geothermal sites, surface geological and geochemical surveys only were conducted.

Under this circumstance, reservoir volumes were determined with the following procedures. Table 3.5.3

shows a summary of the procedure.

The target sites were grouped into three categories (i.e. volcano type, caldera type and


3-38

April 2015


graben type) based on the satellite image analysis and site survey; Maximum plane area of each site was first determined. Most likely plane area of each site then was determined with reference to the existing

survey information of Aluto-Langano, Tendaho-Dubti and Corbetti, where MT/TEM survey was already conducted;

The most likely plane area determined above was adjusted to accommodate field conditions in accordance with intensity of geothermal manifestations and/or fractures.

Minimum plane area is assumed as zero.

Table 3.5.3 Determination of Plane Area of Geothermal Reservoir

Typical Landform

Volcano Type Caldera Type Graben Type

1) Site

Dallol, Boina, Damali, Meteka (Ayelu and Amoissa), Dofan, Tulu Moye, Aluto (Langano, Finkilo, Bobesa), Abaya, Fantale, Boseti

Gedemsa, Kone, Nazareth, Corbetti

Tendaho-Allalobeda, Tendaho-Ayrobeda, Tendaho-Dubti, Teo, Danab, Meteka, Arabi, Butajira

2) Maximum area of reservoir

Area of volcanic body Inner area of calderaArea of geothermal manifestations in graben structure

3) Most likely area 20% of Maximum Area 15% of Maximum Area

100% of Maximum Area(Manifestation Area)

4) Site specific bonus point

+ 20% Alteration Bonus+20% Manifestation Bonus+ 20% Fracture Bonus(where observed)

+ 20% Alteration Bonus+ 20% Manifestation Bonus+ 20% Fracture Bonus(where observed)

+ 20% Alteration Bonus+ 20% Manifestation Bonus+ 20% Fracture Bonus(where observed)

5) Minimum area

zero zero zero

ReferencesMT/TEM Result at Aluto-Langano MT/TEM Result at Corbetti MT/TEM Result at Tendaho


3.5.7 Determination of Reservoir thickness

The parameters shown in the Table 3.5.4 were assumed.

Table 3.5.4 Determination of Geothermal Reservoir Thickness

Items Minimum MaximumMost

ProbablyNotes

Depth to Reservoir top(GL-)

0.5 km 1.0 km 0.8 km Existing information was referred to for “most probably” determination

Depth to Reservoir bottom (GL-)

3.0 km 3.0 km 3.0 km －A depth economically reachable by the present or near future technology

Reservoir Thickness 2.5 km 2.0 km 2.2 km －



3-39 April 2015


3.5.8 Determination of Average Reservoir Temperatures

The reservoir average temperatures were proposed in Table 3.5.5 based on the geochemical assessment

conducted by the Master Plan Project.

Table 3.5.5 Average Reservoir Temperatures

Class Min Max Most

Probably Remarks

Class A 240 290 265 6 sites (Tendaho and Aluto) Class B 210 235 260 7 sites (Boseti, Meteka, etc.) Class C 170 220 195 7 sites (Nazareth, Arabi, etc) Class D 130 170 150 2 sites (Gedemusa and Kone)


3.5.9 Geothermal Power Plant Type Assumed

It was assumed that single flash power plant for average reservoir temperature not less than 200 ºC and

binary power plant for average reservoir temperature less than 200 ºC. The Class C geothermal reservoir

includes both temperature categories above 200 ºC and below 200 ºC. For such case, a flash type power

plant was selected from a practical and economical point of view, by assuming that 40% of the

geothermal reservoir would be above 200 ºC. There will be possibilities that double flash type or

Flash/binary combined type may be adopted. However, there will not be sufficient information to

examine such possibilities at this stage; and possible increment due to those option will be minimal

compared to cost impact, thus those examination was not included in this assessment.


Figure 3.5.2 Average Reservoir Temperature and Power Plant Type

3.5.10 Results of reservoir assessment

The assessment results are shown in Table 3.5.6.

The assessment resulted that the most likely value (‘mode’ in statistic term) is 4,200 MW, value at

occurrence probability 80% is 2,000 MW and the value at occurrence probability is 11,000 MW. There

12 geothermal prospects that may have resources more than 100 MW. It is noted that this calculation

results provided the resource estimation of “Inferred level” in principle. However, the total calculation

result (91 MW) of Aluto-1 (Langano) will include 70 MW of ‘Indicated Resource’ and 5 MW of

‘Measured Resource’, because 70 MW has been estimated by a numerical simulation and 5 MW is the

Temperture

Class A

Class B

Class C

Class D

Calculation

100 150 200 250 300

Binary Single Flash

100%

100%

40%

100%


3-40

April 2015


power output of the pilot plant. Similarly, 10 MW of (Indicated resource) that was estimated by a

Pre-feasibility Study (2014) is included in 290 MW of Tendaho-1 (Dubti).

Table 3.5.6 Resource assessment

Unit: MW Target Site

Site No. Cumulative

probability 80% Most Probable

(mode) Cumulative

probability 20% 19 Corbetti 480 960 2400 16 Abaya 390 790 1900 13 Tulu Moye 202 390 1100 18 Boseti 160 320 800 21 Tendaho-1 140 290 660 4 Damali 120 230 760 7 Meteka 61 130 290 2 Tendaho-3 64 120 320

17 Fantale 64 120 320 14 Aluto-2 58 110 290 22 Tendaho-2 47 100 230 3 Boina 56 100 350

20 Aluto-1 49 91 180 9 Dofan 41 86 200

15 Aluto-3 23 50 110 1 Dallol 23 44 120

12 Gedemsa 20 37 100 11 Nazreth 17 33 100 10 Kone 7 14 42 6 Danab 6 11 30 5 Teo 4 9 23 8 Arabi 4 7 36

New/ Divided Site 7-2 Meteka-Ayelu 47 53 250 7-1 Meteka-Amoissa 28 89 150 23 Butajira 6 16 30

Total 2114 4200 10791

Updated After MT/TEM Survey (See Chapter 7)

18 Boseti 175 265 490 22 Tendaho-2 120 180 320

(based on proposed calculation method)


As a reference, the calculation results using the prevailing calculation method in Table 3.5.7. The

calculation was conducted with ‘conversion factor = 0.13 – 0.16” and ‘Reference temperature=150 ºC’.

If the reference temperature should be 180 ºC, the results will be approximately 20% less than those

results.


3-41

April 2015


Table 3.5.7 Comparison of the results of the Prevailing method and Proposed method


OccurrenceProbability 80%

Most likely(mode)



Most likely(mode)


19 Corbetti 480 960 2400 1.12 1.08 1.4116 Abaya 390 790 1900 1.11 1.05 1.4613 Tulu Moye 201.5 390 1100 1.03 0.93 1.5518 Boseti 160 320 800 1.23 1.14 1.7021 Tendaho-1 140 290 660 1.52 1.66 1.354 Damali 120 230 760 1.50 1.53 1.777 Meteka 60.7 130 290 1.12 1.08 1.452 Tendaho-3 63.5 120 320 1.09 1.00 1.39

17 Fantale 63.6 120 320 1.20 1.09 1.6014 Aluto-2 57.8 110 290 1.18 1.10 1.4522 Tendaho-2 47.3 100.4 230 1.10 1.06 1.443 Boina 55.7 100 350 1.33 1.25 1.59

20 Aluto-1 49.4 91.1 180 1.41 1.32 1.157-1 Meteka-Amoissa 27.9 88.9 150 0.65 1.33 1.25

9 Dofan 40.8 86.1 200 1.32 1.35 1.607-2 Meteka-Ayelu 46.5 53.4 250 2.21 1.16 3.2915 Aluto-3 23.1 49.5 110 1.10 1.18 1.171 Dallol 22.6 44 120 1.13 1.07 1.48

12 Gedemsa 19.5 36.6 100 1.00 1.00 1.0011 Nazreth 17.3 32.7 100 1.00 1.00 1.0023 Butajira 5.7 16.35 30 1.00 1.00 1.0010 Kone 7.3 13.7 42 1.00 1.00 1.006 Danab 5.9 11.4 30.2 1.18 1.04 1.445 Teo 4.4 8.6 22.6 1.00 1.08 1.418 Arabi 3.8 6.9 36.1 1.27 0.86 1.57

total 2114.3 4199.65 10790.9 1.17 1.12 1.48

Proposed/PrevailingPrevailing method

Site No.


3-42

April 2015


aster Plan

on D

evelopment of G


Final Report

ρr(kg/m3) Cr(KJ/Kg℃) ρf(kg/m3) Cf(KJ/Kg℃) φ(%) Rg(%) F(%) L(years)2600 1 950 5 5～10 5～20 0.9 30

Most LikelyArea (km2)

Manifestation

Alteration Fracture

Temperature(ABCD)

Minimum+manifestation,Alteration andFractures bonus

Remarkable:increase%



Maximum (=ShallowCase)

Minimum (=Deep Case)

Most Likely

10 Kone D 6.40 4.80 24.10 24.10 0.00 3.60 9.60 0 0 0.2 0.5 1 0.8 3 2.5 2 2.2 170 130 150

11 Nazareth C 6.00 4.80 22.60 22.60 0.00 3.40 9.00 0 0 0.2 0.5 1 0.8 3 2.5 2 0.88 220 170 195

12 Gedemsa D 8.80 6.60 45.60 45.60 0.00 6.80 36.50 0.2 0.2 0.2 0.5 1 0.8 3 2.5 2 2.2 170 130 150

19 Corbetti B 10.10 15.10 119.80 119.80 0.00 18.00 71.90 0.2 0 0.2 0.5 1 0.8 3 2.5 2 2.2 260 210 235

1 Dallol B 3.00 2.60 6.10 6.10 0.00 1.20 3.10 0.2 0 0 0.5 1 0.8 3 2.5 2 2.2 260 210 235

3 Boina C 11.60 9.20 83.80 83.80 0.00 16.80 25.10 0 0 0 0.5 1 0.8 3 2.5 2 0.88 220 170 195

4 Damali C 16.00 14.50 182.20 182.20 0.00 36.40 54.70 0 0 0 0.5 1 0.8 3 2.5 2 0.88 220 170 195

7-2 Meteka-Ayelu C 8.80 7.80 53.90 53.90 0.00 10.80 27.00 0 0 0.2 0.5 1 0.8 3 2.5 2 0.88 220 170 195

7-3 Meteka-Amoissa C 9.10 8.50 60.70 32.50 0.00 6.50 16.30 0 0 0.2 0.5 1 0.8 3 2.5 2 0.88 220 170 195

9 Dofan B 7.50 6.00 35.30 35.30 0.00 7.10 31.80 0.2 0.2 0.2 0.5 1 0.8 3 2.5 2 2.2 260 210 235

13 Tulu Moye C 20.00 15.00 235.60 235.60 0.00 47.10 117.80 0 0 0.2 0.5 1 0.8 3 2.5 2 0.88 220 170 195

14 Aluto-2 (Aluto-Finkilo) A 4.30 2.72 11.70 11.70 0.00 2.30 5.90 0.2 0 0 0.5 1 0.8 3 2.5 2 2.2 290 240 265

15 Aluto-3 (Aluto-Bobesa) A 2.30 1.50 3.45 3.50 0.00 0.70 3.20 0.2 0.2 0.2 0.5 1 0.8 3 2.5 2 2.2 290 240 265

16 Abaya B 12.50 12.50 122.70 90.00 0.00 18.00 63.00 0.2 0 0.2 0.5 1 0.8 3 2.5 2 2.2 260 210 235

17 Fantale C 11.00 7.30 63.10 63.10 0.00 12.60 44.20 0.2 0 0.2 0.5 1 0.8 3 2.5 2 0.88 220 170 195

18 Boseti B 8.40 6.70 44.20 44.20 0.00 8.80 22.10 0 0 0.2 0.5 1 0.8 3 2.5 2 2.2 260 210 235

2Tendaho-3 (Tendaho-Allalobeda)

A 1.72 0.97 1.30 13.00 0.00 1.30 6.50 0.2 0 0.2 0.5 1 0.8 3 2.5 2 2.2 290 240 265

5 Teo B 0.50 0.30 0.12 1.20 0.00 0.12 0.60 0.2 0 0.2 0.5 1 0.8 3 2.5 2 2.2 260 210 235

6 Danab B 0.70 0.30 0.16 1.60 0.00 0.16 0.80 0.2 0 0.2 0.5 1 0.8 3 2.5 2 2.2 260 210 235

7 Meteka B 2.30 0.80 1.40 14.00 0.00 1.40 9.80 0.2 0.2 0.2 0.5 1 0.8 3 2.5 2 2.2 260 210 235

8 Arabi C 1.90 0.60 0.90 9.00 0.00 0.90 0.90 0 0 0 0.5 1 0.8 3 2.5 2 0.88 220 170 195

21Tendaho-1 (Tendaho-Dubti)

A 3.00 1.00 2.40 24.00 0.00 2.40 16.80 0.2 0.2 0.2 0.5 1 0.8 3 2.5 2 2.2 290 240 265

22Tendaho-2 (Tendaho-Ayrobera)

A 1.30 0.80 0.82 8.20 0.00 0.82 5.70 0.2 0.2 0.2 0.5 1 0.8 3 2.5 2 2.2 290 240 265

(23) Butajira B 1.20 0.70 0.66 6.60 0.00 0.66 3.30 0.2 0 0.2 0.5 1 0.8 3 2.5 2 2.2 260 210 235

MT 20 Aluto-1 (Aluto-Langano) A 2.55 1.18 3.01 6.00 1.05 － 4.80 0.2 0.2 0.2 0.5 1 0.8 3 2.5 2 2.2 290 240 265

Vo

lcan

o t

yp

e

Minimum(℃)

Gra

ben

Ty

pe

MostLikely(℃)

Cal

der

a T

yp

e

Reservoir Temperature Type No Site name20%

(Volcano),15%

(Caldera) ofMaximum

Inner Dia.(Long: km)

Length ofmajor axis（GrabenType:km）

Inner Dia(Short: km)

Length ofmino axis（GrabenType: km）

Area(km2)

MaximumArea (km2)

MinimumArea (km2)

Upper Depth(- km from surface)

BottomDepth (- kmfromsurface)

MaximumThickness(km)

Area of Reservoir (km2) Thickness of Reservoir (km)MinimumThickness(km)

Most LikelyThickness(km)

Maximum(℃)

Table 3.5.8 Parameters Used for Reservoir Resource Assessment


Nippon Koei C

o., Ltd. JM

C G


o., Ltd Sum


evelopment C

o., Ltd.

3-43

April 2015


(References)

Aquater, 1980. Geothermal resources exploration project- Tendaho area. Feasibility study- phase ii.

Final report.

Aquater, 1991. Teodaho geothermal study project: Geothermal study of the Dubti and Allallobeda

geothermal areas in the Tendaho graben (Ethiopia).

Arnórsson, S., 2000. The quartz and Na/K geothermometers. I. New thermodynamic calibration, World

Geothermal Congress, 929-934.

Arnórsson, S., Gunnlaugsson, E., Svavarsson, H., 1983. The chemistry of geothermal waters in Iceland.

III. Chemical geothermometry in geothermal investigations. Geochimica et Cosmochimica

Acta 47(3), 567–577.

Australian Geothermal Energy Group Geothermal Code Committee, 2010. Geothermal Lexicon For

Resources and Reserves Definition and Reporting

Caroline Le Tuldu, Jean-Jacques Tiercelin, Elisabeth Gibert, Yves Travi, Kiram-Eddine Lezzar,

Jean-Paul Richert, Marc Massault, Francoise Gasse, Raymonde Bonnefille, Michiel Decobert,

Bernard Gensous, Vincent Jeudy, Endale Tamrat, Mohammed Umer Mohammed, Koen

Martens, Balemwal Atnafu, Tesfaye Chernet, David Williamson, Maurice Taieb, 1999. The

Ziway-Shala Lake basin system, Main Ethiopian Rift: Influence of volcanism, tectonics and

climatic forcing on basing formation and sedimentation. Palaeogeography, Palaeoclimatorogy,

Palaeoecology Vol. 150, p135-177.

Colin F. Williams 2004. Development of revised techniques for Assessing Geothermal Resources

D'Amor, F. and Panichi, C., 1980. Evaluation of deep temperature of hydrothermal systems by a new gas

geothermometer. Geochimica et Cosmochimica Acta. 44(3), 549–556.

D'Amore, F., Giusti, D., and Gizaw, B., 1997, Geochemical assessment of the Northern Tendaho Rift,

Ethiopia. Proceedings of 22nd Workshop on Geothermal Reservoir Engineering Stanford

University, Stanford, CA, USA, January 27-29, 1997, SGP-TR-155, 435-445.

EIGS-IAEA Project, ETH/8/003, Reports.

ELC/Geotermica Italiana, 1987. Geothermal reconnaissance study of selected sites on the Ethiopian rift

system: Fluid geochemical report.

Fournier, R.O., Truesdell, A.H., 1973. An empirical Na–K–Ca geothermometer for natural waters.

Geochimica et Cosmochimica Acta 37(5), 1255–1275.

Fournier, R. O., 1979, Revised equation for the Na/K geothermometer. Transactions - Geothermal

Resources Council, 3, 221-224.


3-44

April 2015


Giday WoldeGabriel, James L. Aronson, Robert C. Walter, 1990. Geology, geochronology, and rift basin

development in the central sector of the Main Ethiopia Rift. Geological Society of America

Bulletin Vol. 102, p439-458.

Giggenbach, W. F., 1988, Geothermal solute equilibria. Derivation of Na-K-Mg-Ca geoindicators.

Geochimica et Cosmochimica Acta, 52, 2749 - 2765.

Giggenbach, W. F., 1991. Chemical techniques in geothermal exploration. Application of geochemistry

in geothermal reservoir development(coordinator D’ Amore, F., Ed.). UNITAR/UNDP Centre

on Small Energy Resources, Rome., 119-144.

Giggenbach, W.F., 1996. Chemical composition of volcanic gases, in: R. Scarpa, R., and Tilling, R.I.

(Eds.), Monitoring and Mitigation of Volcano Hazards. Springer, pp. 221 – 256.

Gioia Falcone, 2013. Classification and Reporting Requirements for Geothermal Resources

Gizaw, B., 1989. Geochemical investigation of the Aluto-Langano geothermal field, Ethiopian rift

valley. M. Phil., University of Leeds, England, 1-237.

Gonfiantini R., Borsi, S., Ferrara, G., and Panichi, C. , 1973. Isotopic composition of waters from the

Danakil depression (Ethiopia). Earth and Planetary Science Letters 18(1), 13-21

Hot Dry Rocks Pty Ltd, 2013. Global Review of Geothermal Reporting Terminology

Japan International Cooperation Agency, 2011. The Study on Groundwater Resources Assessment in the

Rift Valley Lakes Basin in the Federal Democratic Republic of Ethiopia, Final Report.

K.C. Lee, 1996. Classification of Geothermal Resources – An Engineering Approach

Leśniak, P. M., Sakai, H., Ishibashi, J., and Wakita, H., 1997, Mantle helium signal in the West

Carpathians, Poland. Geochemical Journal, 31, 383-394.

Malcolm A. Grant. Paul F. Bixley 2011. Geothermal Reservoir Engineering Second Edition

Malcolm A Grant 2014. Stored-heat assessments: a review in the light of field experience

Panichi, C., 1995, IAEA Report of an expert mission, Isotopic investigation in geothermal hydrology,

Project No. ETH/8/003.

P. Muffler – R. Cataldi 1977. Methods for Regional Assessment of Geothermal Resources

Seifu, A., 2006, Aluto Langano well status, Go devil and Kuster K10 logs results, 33p.

Subir K. Sanyal, 2005. Classification of Geothermal Systems – A Possible Scheme

UNDP, 1973. Geology, geochemistry and hydrology of hot spring of the east African rift system within

Ethiopia. UNDP Technical Report, New York.


3-45

April 2015


UNDP, 1976. Geochemical investigation in the Lakes District and Afar of Ethiopia. UNDP Report.

UNDP, 1977. Isotopic geochemistry and hydrology of geothermal areas in Ethiopian rift valley.UNDP

Technical Report.

USGS Circular 790 1978. Assessment of Geothermal Resources of the United States


3-46

April 2015


CHAPTER 4 ENVIRONMENTAL AND SOCIAL CONSIDERATIONS

4.1 Outline of Environmental and Social Impact Assessment Study

The Environmental and Social Impact Assessment (ESIA) study was conducted to evaluate potential

environmental impacts due to the geothermal energy development at Initial Environmental Examination

(IEE) level with a comparison of several alternatives. Outline of the ESIA study is as follows.

4.1.1 Tasks of ESIA Study

The ESIA Study consists of the following six main tasks.

(1) Baseline survey (collection and compilation of readily available data and information, and

literature review);

(2) Study on alternative plans applying the concept of strategic environment assessment (SEA)

for the 16 candidate sites mentioned below;

(3) Scoping of the environmental impacts caused by the Project activities;

(4) Prediction and assessment of natural and socio-environmental impacts caused by the Project

in the level of initial environmental examination (pre-IEE);

(5) Mitigation and monitoring plan study; and

(6) Stakeholders’ meeting.

4.1.2 Objectives of ESIA Study

The main objectives of the ESIA Study are as follows:

- To collect natural and social environmental baseline information in order to identify and

assess the potential impacts caused by the Project.

- To identify and assess potential impacts on the social/natural environment and pollution

caused by the Project, and to prepare the management and monitoring plan for necessary actions

toward the potential environmental and social impacts as well as to proposed mitigation

measures.

The main point of the ESIA Study is to collect and compile the environmental-related data and

information in and around the Project sites which enable the JICA Project Team to prioritize the

candidate sites for the geothermal plant development.


4-1

April 2015


4.1.3 Area Covered in the ESIA Study

The study area for the ESIA Study shall cover areas affected by the Project including power

transmission line where differs by item of environmental and social considerations. The Project

includes sixteen (16) target sites in total selected by JICA Study Team and GSE from twenty two (22)

candidate sites shown in Table 4.1.1.

Table 4.1.1 The Target Sites

No. Geothermal Sites Group Site Survey 1 Dallol

Gro

up-2

GSE 2 Tendaho -3 (Allalobeda) JICA 3 Boina GSE 4 Damali (Dam Ali) GSE 5 Teo GSE 6 Danab GSE 7 Meteka JICA 8 Arabi GSE 9 Dofan

Gro

up-1

JICA 10 Kone JICA 11 Nazareth JICA 12 Gedemsa JICA 13 Tulu Moya - 14 Finkilo (Aluto 2) JICA 15 Bobesa (Aluto 3) JICA 16 Abaya - 17 Fantale

Add

ition

al

- 18 Boseti JICA 19 Corbetti - 20 Aluto-1 - 21 Tendaho-1 (Dubti) - 22 Tendaho-2 (Ayrobera) JICA

JICA: The sites where JICA Study Team undertook the site survey. GSE: The sites where GSE undertook the site survey due to access and/or security issues.

Source: JICA Study Team

Among the above 22 sites, the sites from #01 to #16 are included the RD (11 June 2013), the sites from

#18 to #22 are newly included in the Master Plan Formulation project as a result of IC/R meeting held on

14th October 2013 at GSE head office and other follow-up meeting.

4.2 Environmental Laws and Regulations

4.2.1 Framework of environmental and social laws and regulations

Ethiopia adopted its Constitution in 1995, which provides the basic and comprehensive principles and

guidelines for environmental protection, and management. The concept of Sustainable Development

and Environmental Rights are enshrined in Articles 431, 442 and 923 of the Constitution of FDRE4.

Based on the Constitution, several laws and regulations which concern the development of geothermal

energy have been enacted. Among these laws and regulations, “Environmental Impact Assessment

1 Article 43: the Right to development, 2 Article 44: Environmental Rights, 3 Article 92: Environmental Objectives


4-2

April 2015


Proclamation no. 299/2002” (EIA Proclamation) and “Environmental Pollution Control Proclamation

no. 300/2002” are the most concerned proclamations applicable to the development of geothermal

energy. The EIA Proclamation provides EIA with mandatory legal prerequisite for the implementation

of major development projects, programs and plans. This proclamation is a proactive tool and a

backbone to harmonizing and integrating environmental, economic and social considerations into a

decision making process in a manner that promotes sustainable development. The Environmental

Pollution Control Proclamation was promulgated with a view to eliminate or, when not possible to

mitigate pollution as an undesirable consequence of social and economic development activities. This

proclamation is one of the basic legal documents, which need to be observed as corresponding to

effective EIA administration.

As for the framework of resettlement and land acquisition issue, the Constitution (1995) provides basic

policy on the private asset and its compensation. “Expropriation of Landholding for Public Purposes and

Payment of Compensation Proclamation, Proclamation No. 455/2005” and “Payment of Compensation

for Property Situated on Landholdings Expropriated for Public Purposes, Council Ministers Regulation

No. 135/2007” provide the detail procedure such as expropriation process and compensation standard.

Major Regulations, Guidelines and Proclamations applicable to the geothermal energy development

project are listed in Table 4.2.1 below. The contents of listed regulations are summarized in Appendix

4.1.

Table 4.2.1 Major Regulations, Guidelines and Proclamations Applicable to the Geothermal Energy Development Project

No. Title No. Date of Issue 1 Environmental Impact Assessment Proclamation 299 31 Dec, 2002 2 Environmental Pollution Control Proclamation 300 03 Dec, 2002 3 Environmental Protection Organs Establishment Proclamation 295 31 Oct, 2002

4 Expropriation of Landholdings for Public Purposes and Payment of Compensation Proclamation

455 15 Jul, 2005

5 Rural Land Administration and land Use Proclamation, Proclamation 456 15 Jul, 2005 6 Ethiopian Water Resource Management Proclamation 197 Mar, 2000 7 Solid Waste Management Proclamation 513 12 Feb, 2007 8 Environmental Impact Assessment Procedural Guideline Series 1 Nov, 2003

9 Draft EMP for the Identified Sectoral Developments in the Ethiopian Sustainable Development & Poverty Reduction (ESDPRP)

01 May, 2004

10 Investment Proclamation 280 02 Jul, 2002

11 Council of Ministers Regulations on Investment Incentives and Investment Areas Reserved for Domestic Investors

84 07 Feb, 2003

12 The FDRE Proclamation, “Payment of Compensation for Property Situated on Landholdins Expropriated for Public Purposes”

455 2005

13 Council of Ministers Regulation, “Payment of Compensation for Property Situated on Landholdins Expropriated for Public Purposes”

135 2007

14 Oromya Regional Administration Council Directives, “Payment of Compensation for Property Situated on Landholdins Expropriated for Public Purposes” 5 2003

15 Investment (Amendment) Proclamation 373 28 Oct, 2003


4-3

April 2015


(1) Environmental Impact Assessment

1) Laws and regulations relating to EIA in Ethiopia

In order to manage and avoid and/or minimize negative impacts on the natural and social environment

with the implementation of various development projects as well as to promote positive impacts, EIA

has been developed. Its use has been adopted into planning regulations in a number of countries

including Ethiopia. The EIA Proclamation no. 299/2002 aims to ensure that environmental impact

assessment is used to predict and manage the environmental effects of development activities resulting

from their design, citing, installation and operation. EIA is a law-based procedure, and the EIA

Proclamation no. 299/2002 and “Environmental Impact Assessment Procedural Guideline Series 1,

November 2003” issued by the EPA have made EIA procedures compulsory5 to obtain approval for

major development projects. According to the EIA Procedural Guideline, projects are categorized into

three schedules:

Schedule-1: Projects, which may have adverse and significant environmental impacts and therefore

require a full Environmental Impact Assessment.

Schedule-2: Projects whose type, scale or other relevant characteristics have potential to cause some

significant environmental impacts but are not likely to warrant a full EIA study.

Schedule-3: Projects which would have no impact and do not require an EIA.

Projects for geothermal power plant fall under the schedule I activities.

Development activities such as geothermal resource development to be designated by directive require,

before their implementation, the authorization of the EPA, in case of projects that are licensed by the

Federal Government or where they would be likely to have trans-regional environmental impact.

Regional environmental agencies have that authority in the case of projects that are licensed at the

regional level. The authorization would be based on an Environmental Impact Study (EIS) provided by

the project proponent. The EIS is required to meet requirements specified by the EPA directive as to the

issues to be addressed. Project owners are required to consult with the communities likely to be affected

by the project.

2) EIA Process

The general description of the EIA process and the permit requirements are detailed in the EIA

Procedural Guideline Series 1 of the FDRE. As per the Guidelines, it involves sufficient information that

enable the determination of whether and under what conditions the project shall proceed. Thus, as a

minimum, the following descriptions shall be presented:

5 Appendix 1 of the EIA Procedural Guideline Series 1, Schedule of Activities, prescribes that the thermal water extraction projects which exceed 25 Mega Watt, or geothermal steam capable of generating equivalent power for industrial and other purposes are required full EIA.


4-4

April 2015


the nature of the project, including the technology and processes to be used and their physical

impacts;

the content and amount of pollutants that will be released during implementation as well as

during operation;

source and amount of energy required for operation;

characteristics and duration of all the estimated direct or indirect, positive or negative impacts

on living things and the physical environment;

measures proposed to eliminate, minimize, or mitigate negative impacts;

a contingency plan in case of accidents; and,

procedures of internal monitoring and auditing during implementation and operation.

Figure 4.2.1 shows the outline of process and procedures of EIA in Ethiopia. Detailed EIA procedural

flow is shown in Appendix 4.2.


4-5

April 2015


Figure 4.2.1 Outline of Process and Procedures of EIA in Ethiopia

SUBMIT APPLICATION TO ACCESSMENT AGENCIES

ACCEPT

REJECT

PRE-SCREENING CONSULTATION

SCREENING

REVIEW SCREENING REPORT CONSULTATION

ACCEPT

DECISION

SCOPING

REVIEW SCOPING REPORT CONSULTATION

AMEND

AMEND

ACCEPT

DECISION

EIA

REVIEW EIS

AMEND

ACCEPT

DECISION

APPROVED

NOT APPROVED

CONDITION OF APPROVAL

IMPLEMENTATION AUDIT

RECORD OF DECISION

APPEAL

Source: Environmental Impact Assessment Procedural Guideline Series 1, 2003

PROPOSAL TO UNDERTAKE ACTIVITY/INVESTMENT


4-6

April 2015


(2) Environment related standards and Limit Values

For the preservation of the national environmental quality, the EPA of FDRE set national environmental

quality standards for air, water, noise, etc. The EPA also provided industrial pollution control standards

in order to manage negative impacts on the environment caused by the industrial and economical

projects or programs. But some of these standards remain still in draft form at present. In such cases,

International Standards are commonly relied upon. Geothermal energy development projects should

follow these standards at the implementation of projects. In case where sector specific standards are not

available, then general standards for industrial effluent and for gaseous emission are adopted from other

countries such as South Africa or international ones. Table 4.2.2 to Table 4.2.7 below summarize the

Ethiopian and the World Bank’s standards of Environmental, Health, and Safety Guidelines (EHS)

applied to geothermal energy development projects.

Table 4.2.2 Draft Standards for Industrial Emission and Effluent Limits (Ethiopian EPA)

Parameter Unit Draft Standard

Discharge of Wastewater

pH - 6 – 9 BOD5 at 20℃ mg/L 25 COD mg/L 150 Total Phosphorous P mg/L 5 Suspended solids mg/L 50 Mineral oil at the oil trap/interceptor mg/L 20

Emission of pollutant

Total particulates mg/Nm3 150 SO2 mg/Nm3 1,000 NO2 mg/Nm3 2,000

Source: Ethiopia EPA

Table 4.2.3 Draft Standards for Ambient Air Condition (Ethiopian EPA)

Parameter Average time Standard (μg/m3)

SO2 10 min 500 24 hr 125 1 yr 50

NO2 24 hr 200 1 yr 40

CO 15 min 100,000 30 min 60,000

1 yr 30,000

PM10 24 hr 150 1 yr 50


Table 4.2.4 National Noise Standard at Noise Sensitive Areas

Area Category Limits in dB(A) Leq

Remark Day time Night time

Industrial 75 70 Day time: from 6 am to 9 pm Night time: from 9 pm to 6

am Commercial 65 55 Residential 55 45

(Note: Noise sensitive areas include domestic dwellings, hospitals, schools, places of worship, or areas of high amenity)



4-7

April 2015


Table 4.2.5 EHS Guidelines for Emission Gas

Pollutants Units Value Particulate matter mg/Nm3 30 (a)

Dust mg/Nm3 50 SO2 mg/Nm3 400 NOx mg/Nm3 600 HCl mg/Nm3 10 (b)

Total organic carbon mg/Nm3 10 Dioxins-Furans mg TEQ/Nm3 0.1 (b)

Total metals mg/Nm3 0.5 Notes

(*) Emissions from the stack unless otherwise noted. Daily average values corrected to 273K, 101.3 kPa, 10 percent O2 and dry gas, unless otherwise noted. 10 mg/Nm3, if more than 40 percent of resulting heat release comes from hazardous waste. if more than 40 percent of resulting heat release comes from hazardous waste average values over the sample period of a minimum of 30 minutes and a maximum of 8 hours. (c) Total metals: Arsenic (As), Lead (Pb), Cobalt (Co), Chromium (Cr), Copper (Cu), Manganese (Mn), Nickel (Ni), Vanadium (Vn), and Antimony (Sb)

Source: EHS Guidelines

Table 4.2.6 EHS Guidelines for Effluent

Pollutants Units Value pH - 6 – 9

BOD mg/L 30 COD 125

Total Nitrogen 10 Total Phosphorous 2

Oil and Grease 10 Total suspended solids 50 Total coliform bacteria MPN/100ml

(b) 400 (a)

Notes Not applicable to centralized, municipal, waste water treatment systems which are included in guidelines for Water and Sanitation EHS MPN: Most Probable Number


Table 4.2.7 EHS Guidelines for Noise Management Receptor Day time Night time

07:00 – 22:00 22:00 – 07:00 Residential, institutional,

educational (a) 55 45

Industrial, commercial 70 70 (*) Guidelines values are for noise levels measured out of doors. Source: Guidelines for Community Noise, WHO, 1999 For Acceptable indoor noise level for residential, institutional, and educational settings, WHO, 1999


(3) Legislation related to the resettlement and land acquisition

Geothermal Power Generation Plant requires construction of the geothermal production well,

reinjection well (to return waste hot water to underground), pipeline, geothermal generation facilities

such as steam separator, vapor turbine, generator, cooling tower, generating facilities, transformer


4-8

April 2015


facilities for transmission into the electrical grid, etc. In order to accommodate those facilities,

adequate scales of the land are requires and those may associate with the land acquisition.

Constitution (1995) assure right of private property for citizen but not land ownership. The land is

recognized as public common property and its usufruct right can be processed, sold and transferred by

citizens. Also, farm land can be used by the citizen freely as long as the person possess the rural land use

right. “Federal Democratic Republic of Ethiopia Rural Land Administration and land Use Proclamation,

Proclamation No.456/2005” provides the rural land use right. The law also prescribes the governmental

responsibility that regional government have obligation to organize adequate legislative administration

under the central governmental policy. Hens, related to the farm land, regional governments work for

the grant and management of the rural land use right.

Principle of the land acquisition for the public purpose is provided in the constitution (1995) and the

detail procedure such as expropriation process and compensation standard are prescribed in “the

Expropriation of Landholding for Public Purposes and Payment of Compensation Proclamation,

Proclamation No. 455/2005”. “Payment of Compensation for Property Situated on Landholdings

Expropriated for Public Purposes, Council Ministers Regulation No. 135/2007” also provides further

detail standard such as compensation standard for the each expropriating asset.

According to the regulation (2007), land expropriation is implemented by local government, Woreda or

Urban administration exclusively for the public purpose and it should be adequately compensated to

PAPs. As the principle of the compensation, transferring cost for the asset on the land is compensated

for the residential land and 10 times of the annual income which is averaged the incomes in last 5 years

is compensated for the farm land. The one of the preferable way, the regulation prescribes that

provision of the alternative land which enable to be utilized equal to the previous land.

(4) Gaps between Ethiopian Legislations and JICA Guidelines (2010) Policies on Environmental Assessment

From the above discussions, it can be concluded that the JICA Environmental guidelines and the

legislation in the country do not have major contradiction, except perhaps certain procedural

adjustments during project implementation such as public consultation and public disclosure. Appendix

4.3 shows the gaps between current relevant regulations in Ethiopia and JICA Guidelines for

Environmental and Social Considerations (April, 2010) as well as Safeguard Polices in the World Bank.

4.2.2 Institutional Framework of Environmental Management in FDRE

The Federal Democratic Republic of Ethiopia (FDRE) consists of 2 chartered cities, namely Addis

Ababa and Dire Dawa, and 9 regional states. Proclamations 33/1992, 41/1993 and 4/1995 define the

duties and responsibilities of the regional states which include planning, directing and developing social

and economic development programs as well as protection of natural resources. The most important step

in setting up the legal framework for the environmental in Ethiopia has been the establishment of the

Environmental Protection Authority (EPA). The EPA, which has been established under the


4-9

April 2015


proclamation no. 295/2002, is now a ministerial level environmental regulatory and monitoring body.

The objectives of the EPA are to formulate policies, strategies, laws and standards, which promote social

and economic development in a manner that enhance the welfare of humans and the safety of the

environment sustainably, and to spearhead in ensuring the effectiveness of the process of their

implantation. It is, therefore, the responsibility of the EPA in the EIA process to:

ensure that the proponent complies with requirements of the EIA process;

maintain co-operation and consultation between the different sectoral agencies throughout the EIA

process;

maintain a close relationship with the proponent and to provide guidance on the process; and

evaluate and take decisions on the documents that arise from the EIA process.

On the other hand, the regional environmental agencies are responsible for:

Adopt and interpret federal level EIA policies and systems or requirements in line with their

respective local realities;

Establish a system for EIA of public and private projects, as well as social and economic

development policies, strategies, laws, or programs of regional level functions;

Inform EPA about malpractices that affect the sustainability of the environment regarding EIA and

cooperate with EPA in compliant investigations;

Administer, oversee, and pass major decisions regarding impact assessment of:

projects subject to licensing by regional agency;

projects subject to execution by a regional agency;

projects likely to have regional impacts.

Similar to other developmental projects, the proposed geothermal power plants are subject to several

policies and programs aimed at development and environmental protection. The EPA, in cooperation

with other related organizations such as Ministry of Mines and Ethiopian Electric Power Corporation

(EEPCo), regulates the environmental management system for all projects across the country.

Following shows the major institutions or organizations which concern the development of geothermal

energy.

Regional Government: All prospective sites are located in three regional governments, namely,

Afar, Oromia and Somali regional governments. The Region has Zones and Woredas. Within each

Woreda there is many Kebele. Each administrative unit has its own local government elected by the

people. Feature of these three regional governments are summarized in Table 4.3.1.

The Geological Survey of Ethiopia (GSE): The Geological survey of Ethiopia (GSE), under the

Ministry of Mines, has the organizational mandate and legislative instruments that empower it to

execute geothermal projects to the end of the exploration stage. These include:

Surface exploration

Exploratory drilling


4-10

April 2015


Well testing and feasibility studies

Ministry of Water and Energy (MoWE): The Ministry of Water and Energy is the regulatory

body for the energy sector. Based on the delegation from EPA, the whole draft EIA document shall

be submitted to the Ministry for comments and recommendations. The Ministry will also certify the

implementation of the project and monitor the performance of the development project.

Ethiopian Electric Power Corporation (EEPCo): The Ethiopian Electric Power Corporation

(EEPCo) is a national electricity utility established as a public enterprise by Council of Ministers

regulation No. 18/1997. According to the regulation, EEPCo is mandated to engage in the business

of power generation, transmission, distribution and selling of electric energy and to carry out any

other activities that would enable it to achieve its stated mission.

Pastoralist and Agricultural and Rural Development Office of Regional State: The Ministry of

Agriculture and the EPA have delegated their authority to the regional bureau of Pastoralist and

Agriculture and Rural Development.

Corporate Planning Department of EEPCo: Corporate Planning of EEPCo comprises

environmentalists and sociologists to address environmental and social issues that may arise due to

its operation. The project office shall be instituted in this organization with defined roles,

responsibilities, and authority to implement the socio-environmentally critical actions such as

implementation of EIA, EMP and so on to be undertaken.

4.3 Baseline Survey

4.3.1 Methodology of Baseline survey

Standard methodologies to collect data and information at the prospective geothermal energy

development sites were applied to carry out the study that included primary and secondary data

reviewing. Additionally, the ESIA study team collected data and information at the prospective

geothermal energy development sites using questionnaires, and visiting the governmental and the local

organizations which are responsible for environment, social, economic, cultural, and so on located in

Oromia, Afar and Somali regions. For the implementation of the study above, following eight kinds of

questionnaires were used:

Questionnaire for Kebele level cultural and ecological related questionnaire

Kebele level education related questionnaire

Kebele level health related questionnaire

Kebele level water resource related questionnaire

Kebele level water and energy resource related questionnaire

Questionnaire for household

Kebele level Economic related Questionnaire

Questionnaire for Focus Group Discussion (FGD)- Community CONSULTATIONS


4-11

April 2015


The ESIA study team visited the following 7 Woreda sector offices for the collection of baseline data at

each site.

Agriculture /pastoralist office,

Economic & finance office,

Education office,

Health office,

Culture &tourism office,

Land use and environment office, and

Water & energy office

As for surveys at #4 Damali and #05 Teo in Table 4.1.1, the surveys were conducted only through

data/information collection and literature review, due to the difficulty of accessibility to these two sites.

4.3.2 Outline of the Baseline data

(1) Profile of the Study Area

Data and information collected through the ESIA study have been summarized in terms of the

environmental and the social conditions such as i) natural and geological conditions, ii) socio economic

conditions, and iii) accessibility/road, together with notable potential environmental and social impacts

when geothermal energy development projects are implemented at 15 prospective sites respectively.

Summary table is shown in Appendix 4.4. Major data and information collected are shown below.

The 16 prospective geothermal energy development sites are located either in Afar Depression or

Main Rift Valley. Among the 15 prospective sites, 8 geothermal energy development sites are located

in Afar Depression and the rest 7 sites are located in the Main Ethiopian Rift Valley.

The three study Regional States, namely the regions of Afar, Oromo, and Somali, more or less share

similar features. They border with each other. Oromia borders Afar, Amhara and Benshangul/Gumuz

Regions in the north; in the south Oromia borders Kenya; in the south and in the east Oromia borders

Somali. In the West, Oromia borders Sudan. On the other hand, Afar borders Eritrea in the north-east,

Tigray in the northwest, and Amhara and Oromia in south and south west respectively. Somali

Regional state borders Afar Region and Djibouti in the north, Kenya in the south, Oromia Region in

the west, and Somalia in the east and in the South.

While the bigger size of Afar Region lies within the Ethiopian Rift Valley, only some parts of Oromia

and Somali that lie in the Rift Valley. With respect to population, Oromia Region has the largest figure,

roughly 35, 500,000, followed by Somali, roughly 5,850,000 and Afar, roughly 1,830,000,

respectively. Profiles of the three regions are summarized in the table below (Table 4.3.1).

Table 4.3.1 Profile of Three Regions

Region Afar Oromia Somali

Location Mainly at eastern part of Ethiopia Mainly at the west, south, and Mainly at the eastern and


4-12

April 2015


Region Afar Oromia Somali

eastern part of Ethiopia southeastern of Ethiopia Topography Dominantly low land located

within Great Rift Valley, dominantly, sandy and rocky.

Varied topography, from low land to high lands varied relief features: rugged mountain ranges, plateaus, gorges and deep incised river valleys, and rolling plain.

Mainly low land, about 80% of the topography is flat and sandy.

Climatic conditions

From 25℃during the rainy season (September-March) to 48℃ during the dry season.

Varied with amiable climatic condition, dry, tropical rainy and temperate rainy climate.

Bigger proportion (85%) is dry and hot, characterized by 20℃ to 40℃.

Area 96,707 km2 284,538 km2 279,252 km2 Population 1,828,504 (up dated for 2014) 35,522,174 (up dated for 2014) 5,849,605 (up dated for 2014) Religious More than 90% Muslim More than 90% are proportionally

Muslim and Christians More than 90% Muslim

Language Dominantly Afar but Amharic is widely spoken

Dominantly Oromo language but Amharic is widely spoken

Dominantly Somali but Oromo and Amhara language are widely spoken.

Administration 5 administrative zones and about 30 woredas

12 zones administrative and about 180 woredas

9 administrative zones and more than 45 woredas

Capital city Semera Addis Ababa, defacto Adama (Nazareth)

Jigjiga

Livelihood Mainly cattle rearing/pastoralists Mainly farming Mainly cattle rearing/pastoralists Agri products Maize, beans, sorghum, papaya,

banana, and orange Maize, teff, wheat, barley, peas, bean, oil seed, coffee

Mainly sorghum and maize, and some wheat harvested

Animals 22% of camel, 4% of goats, 2% of sheep, and 1% of cattle

45.4% of cattle, 40% of goats, 38% of sheep, 12% of asses, 31% of camels

2% of cattle, 3% of sheep, 6% of goats, 4% of asses and 37% of camels

National Attractions

Afar Depression-Ertale, Awash and Yangudi Rassal National Parks, Human fossil sites such as Hadar and Ramis

National Parks Bale mountains, the Rift Valley lakes, caves like Sof-Omar and a number of hot springs are located

As part of the great Rift Valley hot springs are located in some parts

Minerals Major minerals include: salt, potash, sulfur, manganese, bentonite, aluminium, marble, gypsum

Gold, soda ash, platinum, limestone, gypsum, clay soil, tantalum, and ceramic

Natural gum, salt, and gas oil

Data source: CSA and other relevant documents

(2) Natural, Historical and Cultural Heritages

In general, there are no natural and historical points found near or around all of the proposed sites.

However, the views the community to the hot springs (in Teo/Kone, Meteka, Boku, and Arabi), the

claims of Orthodox Church (in Boku), and the location of the Orthodox Church (in Meteka) needs

special consideration. The detail is shown in Table 4.3.2.


4-13

April 2015


Table 4.3.2 Natural, Historical and Cultural Heritages

Source: ESIA Study Report

(3) Ecological Protected Area

All legally protected areas such as national park, wildlife reserve and controlled hunting areas are

avoided from the prioritized project sites in the study at the Master Plan establishment stage. The project

contains 15 project sites located in the 3 regions i.e.; Afar, Somali and Oromia regions. The

environmentally important area in Ethiopia is protected as National Parks, Wildlife Reserves and

Controlled Hunting Areas and the areas fallen into the project related 3 regions are shown in the below

table(Table 4.3.3). With the progress of the project stage, further confirmation should be conducted to

minimized impact to those areas.

Table 4.3.3 Distribution of sensitive environmental features surrounding the project



4-14 April 2015


(4) Possible Impacts by Transmission Line

The Project includes the construction of high voltage Power transmission lines. High voltage Power

transmission lines may have an impact on the visual capacities of birds and may result in collisions

depending on sites of installation. Because of the exact routes where the transmission lines are going

to be developed are not yet determined, it is not possible to envisage the degree of the impacts caused

by the installation of the transmission lines on migratory birds. Although the prospective geothermal

development sites in this study are not included in National Parks or Conservation Areas of Ethiopia,

there exist a few National Parks near some prospective sites. The ESIA study revealed that the two

National Parks vicinity to some prospective sites located on important migration flyways. One is

Yangudi Rassa National Park which is in the center of the Afar Region (in northern section of the Rift

Valley) between the towns of Gewanae and Mille, and 500km from Addis Ababa. Yangudi Mountain

lies on its south-eastern boundary, and is surrounded by the Rassa plains. Many migratory species

have been found in this area including Falco naumanni and Circus macrourus, both of which are

recorded regularly on migration during winter season. Another National Park which locates on a

migratory flyway is Abijata-Shalla Park in Oromia Region which was established combining Lakes

Abijata and Shalla. It has several hot springs around the shore, and nine islands of which at least four

are important breeding sites for birds. This Park locates on a major flyway for both Palearctic and

African migrants, particularly raptors, flamingos and other water birds. Detailed migratory flyways

should be investigated in the EIA study for the determination of the routes of high voltage

transmission lines in order to avoid or minimize the impacts on migratory birds.

4.4 Strategic Environmental Assessment (SEA)

Strategic environmental assessment (SEA) is a systematic decision support process, aiming to ensure

that environmental and possibly other sustainability aspects are considered effectively in policy, plan

and program making. Therefore, an SEA is conducted before a corresponding EIA is undertaken. This

means that SEA focuses mainly policy level issues before implementing certain projects or programs.

Although implementation of SEA for development projects is not compulsory at present in Ethiopia,

considering the definition and the concept of SEA mentioned above, SEA for geothermal energy

projects should be discussed the following point of views.

Ethiopian energy policy on geothermal development,

Project alternatives including “do-nothing” option

Project perspective from guidelines of financial institutions,

Alignment of JICA guidelines with national policies

4.4.1 Ethiopian energy policy on geothermal development

(1) Conservation Strategy of Ethiopia (CSE)

Since the early 1990s, the Federal Government has undertaken a number of initiatives to develop


4-15

April 2015


regional, national and sector strategies for environmental conservation and protection based on the

Conservation Strategy of Ethiopia (CSE) approved by the Council of Ministers. The CSE provided a

strategic framework for integrating environmental planning into new and existing policies, programs

and projects. The CSE also provides a comprehensive and rational approach to environmental

management in a very broad sense, covering national and regional strategies, sectoral and cross sectoral

strategy, action plans and programs, as well as providing the basis for development of appropriate

institutional and legal frame works for implementation.

(2) Environmental Policy of Ethiopia (EPE)

The Environmental Policy (EPE) of the FDRE was approved by the Council of Ministers in April

1997based on the CSE. It is fully integrated and compatible with the overall long term economic

development strategy of the country, known as Agricultural Development Led Industrialization (ADLI),

and other key national policies. EPE’s overall policy goals may be summarized in terms of the

improvement and enhancement of the health and quality of life of all Ethiopians and the promotion of

sustainable social and economic development through the adoption of sound environmental

management principles. Specific policy objectives and key guiding principles are set out clearly in the

EPE, and expand on various aspects of the overall goal. The policy contains sector and cross-sector

policies and also has provisions required for the appropriate implementation of the policy itself.

(3) National Energy Development Policy

The National Energy Policy of 1994 has the objective of facilitating the development of energy

resources for economical supply of energy to consumers in an appropriate form and in the required

quantity and quality. The strategies consist of the accelerated development of indigenous energy

resources and the promotion of private investment in the production and supply of energy.

According to the National Energy Development Policy, the main priorities of current energy policy in

Ethiopia are:

Equitable development of the energy sector together with other social and economic developments.

Development of indigenous resources with minimum environmental impact and equitably

distribution of electricity in all the regions.

4.4.2 Energy Resource Alternatives

The Ethiopian Government has embarked upon various plans and programs to explore and develop

different energy resources (i.e., hydropower, geothermal, wind and solar) to achieve the major goals of

accelerating economic growth and reducing poverty. Development of geothermal energy exerts both

positive and negative impacts on the natural and the social environment. There is no combustion process

with geothermal energy plant, geothermal energy is generally accepted as being an environmentally

kind and gentle energy source comparing to fossil fuel energy source. Considering the characteristic of

geothermal energy source, geothermal energy source also has several advantages even compared to


4-16

April 2015


other renewable energy sources. Table 4.4.1 and Table 4.4.2 below show the characteristics and the

advantages of geothermal energy compared to other energy sources.

Table 4.4.1 Environmental Characteristics of Geothermal Energy

Geothermal energy Other renewable energy

Availability/reliability Most reliably available Not rely on uncontrollable outside forces

Such as solar or wind, are only available when the weather cooperates.

Natural condition Less constrained by natural topography for selection of site

Required to meet specific natural condition (effective wind or solar farm)

Land claim Not require as much land to produce equivalent power as do other clean energies.

Roughly 10 times of amount of land is needed for a solar farm to produce the same amount of energy

Cleanness/Cost effectiveness Cleaner, more efficient, and more cost-effective than burning fossil fuels

Burning fossil fuels generate dust, NOx, SOx and other noxious substances

Emission of CO2 and others Geothermal plant releases a less amount of CO2 produced by fossil fuel plant

Fossil fuel plants produce more amount of CO2


Table 4.4.2 Advantages of Geothermal Energy Compared to other Renewable Energy Sources

Characteristics Geothermal Wind Solar Biomass Hydro Base lord capacity ◎ × × ◎ ◎ Unlimited potential ◎ ◎ ◎ × × No fuel costs ◎ ◎ ◎ × ◎ Negligible CO2 emission ◎ ◎ ◎ × Low impact landscape ◎ × × ◎ × Competitive costs ◎ ◎ × ◎ ◎ Capacity factor (%) 89-97 26-40 22.5-32.2 80 - Exploration risk ? ◎ ◎ ◎ ◎

Source: Ultra-deep-geothermal/energy,A Guide to Geothermal Energy and Environment, Geothermal Energy

Association, USA 2007)

Above tables show that geothermal energy is a renewable and environmentally friendly energy

generation option, compared to other energy sources particularly compared with fossil fuel.

Besides the advantages of geothermal energy source above, there are several positive impacts on the

social environment. Main positive impacts of geothermal energy development are: stimulation of

economic growth of the country, improvement of the living standard of the population, benefits to the

local people (temporary employment opportunity) and local economy development. The proposed

geothermal energy development would encourage investors to invest in the region, ultimately creating

more job opportunities. The proposed project will also allow the reduction of carbon dioxide emissions

from electricity generation using renewable geothermal energy instead of other fossil fuel burning

power generation. This suggests that the application of Clean Development Mechanism (CDM) to the

projects.

4.4.3 Project Alternatives

One of the main objectives of SEA is to analyze the alternatives of the proposed project including

“do-nothing” option. To overcome the growing demand, planning for energy diversification is very

important. Therefore, the formulation of geothermal energy development by this study is an important

step to diversify electricity generation which will enable to backup the other energy sources. The impact Nippon Koei Co., Ltd. JMC Geothermal Engineering Co., Ltd Sumiko Resources Exploration & Development Co., Ltd.

4-17

April 2015


caused the implementation of the project on the environment and social is localized and can be

minimized by applying proper mitigation and management measures.

Considering the features of geothermal energy development, possible alternatives at SEA stage could

be:

a "do-nothing" option of the project to consider the environmental conditions in the absence of the

project (without project),

drilling the wells at different depths, to exploit different reservoirs (with project)

Table 4.4.3 below summarizes the advantage and the disadvantage two alternatives above.

Table 4.4.3 Comparison of Alternative

Alternatives Advantage Disadvantage

1

Wit

hout

pro

ject

Do-nothing No additional environmental impacts related to the project

No social and socio-economic benefits to the country. Worsening of the deforestation problem. No promotion educational, commercial and industrial development.

2

Wit

h pr

ojec

t

Drilling wells at different depth

Drilling and exploiting wells only from the deep reservoir

Less or no subsidence risks More expensive, longer solution

Drilling and exploiting wells only from the shallow reservoir

Cheaper and faster solution Subsidence risks

Drilling wells in different location

Drilling in the sites prioritized in this study (Tendaho, Ayrobera)

Higher environmental appropriateness (See Appendix 4.4)

Dispossession of grazing land, water use competition, etc. (See Appendix 4.4)

Drilling in the sites other than above sites

No residential areas (See Appendix 4.4)

Bad accessibility, etc. (See Appendix 4.4)

Source: Tendaho Geothermal Development F/S Report, 2013, Italy

The “no project option” implies that the power plant will not be established at the project site and the site

would continue to remain as it were. No socio-economic benefits would accrue either to the nearby

communities or to the country at large. Choosing the “no project option” therefore will mean loss of

benefit to the nation, what is more, no new employment opportunities would be created.

Selecting the depth / location of wells is very critical for the feasibility of a project. Therefore, proper

and comprehensive analysis of location and site selection shall be carried out utilizing different factors

and criteria.

4.5 Implementation of IEE

An Initial Environmental Examination (IEE) is carried out based on the baseline data and information,

namely readily available information including existing data and simple field surveys.


4-18

April 2015


4.5.1 Project Categorization

(1) General

According to the JICA Environmental Guidelines (April 2010), projects are classified into four

categories depending on the extent of environmental and social impacts, taking into account an outline

of project, scale, site condition, etc. Table below shows the comparison of projects categorization

defined by JICA and Ethiopian national EPA Guideline.

Table 4.5.1 Environmental Categorization of Projects

Project type JICA Guidelines Ethiopia EPA

Guideline EIA requirement

Likely to have significant adverse impacts on the environment and society. Projects with complicated or unprecedented impacts that are difficult to assess, or projects with a wide range of impacts or irreversible impacts

Category A Schedule-1 Full EIA

Have potential adverse impacts on the environment and society are less adverse than those of Category A projects. Generally, they are site-specific; few if any are irreversible; and in most cases, normal mitigation measures can be designed more read

Category B Schedle-2 Not likely to warrant a

full EIA study

Have are likely to have minimal or little adverse impact on the environment and society. Category C Schedule-3

Environmental review will not proceed after

categorization Projects which satisfy the following JICA’s requirements: projects of JICA’s funding to a financial intermediary or executing agency; the selection and appraisal of the sub-projects is substantially undertaken by such an institution only after JICA’s approval of the funding, so that the sub-projects cannot be specified prior to JICA’s approval of funding (or project appraisal); and those sub-projects are expected to have a potential impact on the environment.

Category FI - Environmental review

will proceed after categorization


(2) Classification of geothermal energy development project

Appendix I (Schedule of Activities) of the Environmental Impact Assessment Guideline Document

(May 2000) classifies projects by their type of activities as follows:


4-19

April 2015


Based on the project classification above, geothermal energy development projects which have

capacities more than 25 mega watt may be required the implementation of full scale EIA.

4.5.2 Scoping for Initial Environmental Examination

Geothermal energy is generally more environmentally sound compare to other energy sources such as

fossil fuel burnings, there are certain negative impacts that must be considered and managed when

geothermal energy is to be developed. Following table summarizes the considerable negative impacts

when geothermal energy is developed.

In order to assess likely significant environmental and social impacts, the conceivable adverse

environmental and social impacts by the Project were initially indentified based on the project

description and overall environmental and social conditions in the surrounding area. The impacts of

pollution, natural environment, and social environment were classified from A to D as shown in Table

4.5.2. Most of potentially important impacts of geothermal power plant development are associated

with groundwater use and contamination, and with related concerns about land subsidence and

induced seismicity as a result of water injection and production into and out of a fractured reservoir

formation. Some considerations should also be taken for issues of air pollution, noise, safety, and land

use. Overall environmental Scoping Checklist is shown in Appendix 4.4).

APPENDIX 1: SCHEDULE OF ACTIVITIES (In order of level)

Schedule 1: Project which may have adverse and significant environmental impacts, and may, therefore, require full EIA.

C. Production Sector

11. Minerals extraction and processing (Large scale Mining Operation, Which the annual run of mine ore exceed:)

f. Thermal Water (25 Mega Watt, or geothermal steam capable of generating

equivalent power for industrial and other purposes)

Source: Environmental Impact Assessment Guideline Document, May 2000


4-20

April 2015


Table 4.5.2 Environmental Scoping Checklist for the Project for Formulating Master Plan on Development of Geothermal Energy in Ethiopia project

No Likely Impacts Reason and Description Rating

Social Environment 1 Involuntary

resettlement Planning phase: Land for geothermal plant is required. There are residents in the prospect site area and the impact should be minimized to avoid resettlements and land area. The approximate number of land owner for the prospect sites are 50 persons in total. Detail study should be conducted.

C-

2 Living and Livelihood Construction phase: Surface disturbance of wilderness has high impact as active sites tend to be in rare landscape types of very high scenic and touristic (economic) value including ‘colorful striking landscapes, hot springs, lavas and glaciers. Disturbance includes roads, power lines, factories, heavy lorries and drilling equipment.

B-

Construction phase & Operation phase: Job opportunities for the surrounding area for project sites are increased.

B+

3 Land use and utilization of local resources

Planning phase & Construction phase: The project areas are used mainly as farmland and grazing land, with dispersedly located houses, while few of them (Erabti, Dallol, Derail and Teo) are nearly uninhabited. Meteka, Bobessa, Finkilo, and Dofan sites are populated; particularly Meteka is densely settled by town residents. The rest sites Arabi, Tone, Allelobeda, Boset, Gedemsa and Boku are dominantly used either for cultivation or grazing. One special scenario is the case of Bobessa and Finkilo (Alluto 2 and 3). Here, the site is in adjacent to geothermal power facility which has been under construction by Ethiopian Energy and Power Corporation (EEPC) for the last few years.

B-

Operation phase: The effective land use is expected in the area. B+ 4 The poor, indigenous

and ethnic people No particular indigenous people and ethnic people are identified in the area at the moment. D

5 Local conflicts of interests

No particular impact is envisaged at the moment. D

6 Water usage or water rights and rights of common

Planning phase, Construction phase and Operation phase: The project may be associated with the well drillings such as testing, geothermal production and reinjection wells. Also, construction and operation of power generation plant may require freshwater. The impact should be minimized based on the study at the detail design stage.

C-

7 Hazards(Risks) (infectious disease such as HIV/AIDS)

No particular impact is envisaged at the moment. D

8 Working Conditions No particular impact is envisaged at the moment. D 9 Disaster No particular impact is envisaged at the moment. D Natural Environment 10 Topography and

geographic features Construction phase: Surface disturbance of wilderness has high impact as active sites tend to be in rare landscape types of very high scenic and toursitic (economic) value including ‘colourful striking landscapes, hot springs, lavas and glaciers. Disturbance includes roads, power lines, factories, heavy lorries and drilling equipment.

B-

11 Land subsidence Operation phase: Subsidence, or the slow, downward sinking of land, may be linked to geothermal reservoir pressure decline. Injection technology, employed at all geothermal sites in the United States, is an effective mitigating technique.

B-

12 Climate Operation phase: Local weather changes caused by emission of steam affecting clouds. B- 13 Soil erosion Construction phase: Landslides can occur due to temperature and water level in rocks,

especially in tectonically active areas. B-

14 Wetlands, rivers and lakes

Planning phase, Construction phase, Operation phase: Some project sites such as Meteka and Kone are located closely to wetland. Some impact may be associated with the project.

B-

15 Fauna and flora and biodiversity

Planning phase and Construction phase: The protected areas are basically avoided for the site selection. For detail survey should be conducted at the implementation of full EIA study (ESIA). Before geothermal construction can begin, an environmental review may be required to categorize potential effects upon plants and animals. Power plants are designed to minimize the potential effect upon wildlife and vegetation, and they are constructed in accordance with a host of state and federal regulations that protect areas set for development.

B-

16 Landscape Construction phase: Surface disturbance of wilderness has high impact as active sites tend to be in rare landscape types of very high scenic and touristic (economic) value including ‘colorful striking landscapes, hot springs, lavas and glaciers. Disturbance includes roads, power lines, factories, heavy lorries and drilling equipment.

B-

17 Ground water Planning phase, Construction phase and Operation phase: The project may be associated with the well drillings such as testing, geothermal production and reinjection wells. Also, construction and operation of power generation plant may require freshwater. The impact should be minimized based on the study at the detail design stage.

C-

Pollution 18 Air pollution Construction phase: Due to construction work in the city area, air quality is likely affected

due to congestion of traffic and other construction machinery. Geothermal power plants release very few air emissions because they do not burn fuel like

B-


4-21

April 2015


No Likely Impacts Reason and Description Rating

fossil fuel plants. Geothermal plants emit only trace amounts of nitrogen oxides, almost no sulfur dioxide or particulate matter, and small amounts of carbon dioxide. The primary pollutant some geothermal plants must sometimes abate is hydrogen sulfide, which is naturally present in many subsurface geothermal reservoirs. With the use of advanced abatement equipment, however, emissions of hydrogen sulfide are regularly maintained below Ethiopian standards. Emissions of H2S –distinguished by its “rotten egg” odor and detectable at 30 parts per billion – are strictly regulated to avoid adverse impacts on plant and human life.

19 Water contamination (Water use & Water contamination)

Planning Phase, Construction Phase and Operation Phase: Liquid streams from well drilling, stimulation, and production may contain a variety of dissolved minerals, especially for high-temperature reservoirs (>230°C) which may not be the case at most of the geothermal prospect areas in Ethiopia. Some of these dissolved minerals (e.g., boron and arsenic) could poison surface or ground waters and also harm local vegetation only in some locations. Liquid streams may enter the environment through surface runoff or through breaks in the well casing. Surface runoff can be controlled by directing fluids to impermeable holding ponds and by injection of all waste streams deep underground. It is important to monitor wells during drilling and subsequent operation, so that any leakage through casing failures can be rapidly detected and managed. Toxic waste water may enter clean aquifers due to lowering of the water table.

B-

20 Wastes Planning Phase, Construction phase and Operation phase: At the detail survey and construction, sludge from the drilling work may be generated. Also, construction waste and general waste at the operation may be generated even those amount are not large. Adequate treatment should be conducted following the standard.

C-

21 Noise and vibration Planning Phase (Well drilling and testing phase): Generally noise generation in this phase does not exceed the Ethiopian noise regulations. Much like the construction phase of development mentioned below, well-drilling and testing are temporary, and the noise pollution they produce is not permanent. It is estimated that well drilling operations would not exceed 54 dBA. However, unlike the construction phase of development, well-drilling operations typically take place 24 hours per day, seven days a week. This temporary noise pollution can last anywhere from 45 to 90 days per well. Construction phase (Noisiest phase): Noise may be generated from construction of the well pads, transmission towers, and power plant. The noisiest phase of geothermal development, but the past experiences show generally remains below 65 dBA. Noise pollution associated with the construction phase of geothermal development is a temporary impact that ends when construction ends. Well pad construction can take from a few weeks or months to a few years, depending upon the depth of the well. In addition, construction noise pollution is generally only an issue during the daytime hours and is not a concern at night. Operation phase: Noise from normal power plant operation generally comes from the three components of the power plant: the cooling tower, the transformer, and the turbine-generator building. It is estimated, noise from normal power plant operation at the site boundary would occupy a range of 15 to 28 dBA—below the level of a whisper Several noise muffling techniques and equipment are available for geothermal facilities. During drilling, temporary noise shields can be constructed around portions of drilling rigs. Noise controls can also be used on standard construction equipment, impact tools can be shielded, and exhaust muffling equipment can be installed where appropriate.

B-

22 Odor Planning phase, Construction phase and Operation phase: Even temporary, emission of hydrogen sulfide (H2S) may associate with the Geothermal production test at detail survey and construction. At the operation, also hydrogen sulfide (H2S) may be discharged. The impact should be minimized based on the study at the detail design stage.

C-

23 Accidents Construction phase and Operation phase: There was an example that violent explosions caused by buildup of a ‘steam pillow’ in empty hot underground reservoirs, which have previously killed people working in geothermal plants. While earthquake activity, or seismicity, is a natural phenomenon, geothermal production and injection operations have at times resulted in low-magnitude events known as ―micro earthquakes.‖ These events typically cannot be detected by humans, and are often monitored voluntarily by geothermal companies.

B-


<Rating> A-: Serious impact is expected, if any measure is not implemented to the impact. B-: Some impact is expected, if any measure is not implemented to the impact. C-: Extent of impact is unknown (Examination is needed. Impact may become clear as study progresses.) D : No impact is expected. A+: Remarkable effect is expected due to the project implementation itself and environmental improvement

caused by the project. B+: Some effect is expected due to the project implementation itself and environmental improvement caused by

the project.


4-22

April 2015


4.5.3 Socio-environmental Interactions

In order to grasp the livelihood conditions in and around the prospective sites, questionnaire surveys for

energy and water sector offices at woreda levels were conducted. In this questionnaire surveys,

interviewee were professionals, experts and guidelines about the proposed geothermal projects and

related issues.

With respect to energy, in few households kerosene lamps and solar cells are becoming to be used

particularly in health posts and schools. However, the survey revealed that the main source of energy

both for cooking and light was fuel wood, coal and dung. The impact of wide use of wood and coal

would be not significant as the number of rural community is few and scattered, compared to the

available resource and its regenerative capacity. In addition to this, energy consumption per capita of

the community is very low. Social impacts such as unnecessary time and labor wastage should also be

addressed.

With regard to water source and supply, in most of the surveyed sites except Tendaho-3 (Alallobeda),

Arabi, Dofan, Meteka, and Kone, there is critical shortage of sufficient and uninterrupted water supply.

But in all other sites, access to potable (treated) water is still a priority. Water resource competition

from currently growing (expanding) sugar industries is pessimistically perceived by the community. In

addition to this, some individual investors use water from hot springs/when available for irrigation. So

there seemed water resource competition and fast land use change in some of the surveyed areas.

Respondents were asked about the negative impact of the project on water in terms of pollution, water

supply/ system; the possible competition of the project for the existing water resources; and options to

reduce or avoid the impacts. The finding revealed that the community believed the project would bring

about little negative impact. However in terms of the serious shortage of water all community in all

sites required the supply of water at least in their respective kebeles. Thus there is a strong need of

residents to implement community projects to access potable water source (characterized by

community participation in collaboration with other development organizations), parallel to the main

geothermal project.

Table 4.5.3 below summarizes the conditions of the livelihood in fifteen (15) prospective sites.

Table 4.5.3 Livelihood at the prospective sites

No. Site Livelihood

1 Dallol Wage and revenue earned from salt mining and transporting the commodity is the back bone of the livelihood of the community of Amed-ale. And yet since what is earned doesn’t cover households’ living expense, large proportions of them are under food relief program.


The community is totally dependent on subsistence livestock. Thus food security in the woreda is seriously threatened. Thus since there is no farming practiced across the kebele, the community is under food relief assistance throughout the year.

3 Boina Bahri kebele is entirely dependent on subsistence livestock breeding and therefore agriculture is not practiced. As food security is seriously threatened, the community relies on food support distributed by the Government.

4 Damali Located in the Afar region at the central part Afar depression, administrated by Asayta Woreda. The area is in arid and dry land which has also very low and erratic rain fall pattern with below 300 mm precipitation. Located at low altitude, which is in between 250 500 meter above sea level.


4-23

April 2015


No. Site Livelihood

5 Teo

Located in the Afar region at the central part Afar depression, administrated by Mile Woreda. The area is in arid and dry land which has also very low and erratic rain fall pattern. The annual rain fall ranges between 300 – 500 mm precipitation. Located at low altitude, which is in between 250 - 500 meter above sea level.

6 Danab

Located in the Afar region at the central part Afar depression, administrated by Dubti Woreda. The area is in arid and dry land which has also very low and erratic rain fall pattern. The annual rain fall ranges between 300 – 500 mm precipitation. Located on the next elevated mountain plateau which have relatively high altitudes ranging 500 – 800 meter above sea level.

7 Meteka

Unlike other kebeles, Meteka is semi-urban small town. Thus, although agriculture is practiced in most other kebeles, the community of Meteka is either employed in different sectors or engaged in small businesses. As per the information obtained from the woreda office, the revenue that most residents generate from their business/employment hardly covers their costs of living. Due to this, some of the households are regular receivers of food assistance.

8 Arabi

The main agricultural activities (both commercial and subsistence) of the kebele are livestock keeping and crop production. In the areas surrounding the project site, the major cash crops produced are maize, sorghum, tomato, onion and fruits. The assessment reveals absence of big farms; what is more, neither animal husbandry, nor livestock keeping is dominant. Although, people living in the small town of Arabi engaged in the production of different kinds of fruits, the kebele is characterized by food insecurity mainly due to poor weather conditions, lack of water and infertility of the land. Relief food has been granted by the Ethiopian Government for the victims throughout the year. As reported, food prices increase as the result of more demand to food items. This poses a significant challenge for those pastoralists who never engaged in crop production and fully relied in purchasing food items

9 Dofan The communities of Dofan live on livestock breeding, though insignificant numbers of them are wage earners in big government and private farms. As many of Afar kebeles, the pastoralists of Dofan are not food secured thus receive food assistant regularly.

10 Kone

The livelihood of the community is based on subsistent farming and livestock keeping. In the areas surrounding the project site, the community is self sufficient in food. Using the available inconsistent rain some of the kebele dwellers produce cash crops including maize, tomato, onion and fruits.

11 Nazareth As far as food insecurity is concerned Boku kebele is relatively safe. Although part of the community is still far below the poverty line, the kebele is categorized under food secured kebeles and doesn’t receive food assistance from the government.

12 Gedemsa

The principal economy of the kebele is derived from agriculture products. Despite the inconsistent rain, absence of water and lack of irrigation practice, the kebele is one of the few areas known for food sufficiency. A better strategy such as supply of agricultural inputs, and access to water can increase productivity and could sustain the present status of food security.

14 Aluto-2

(Altu-Finkilo) Agriculture is the dominant means of livelihood in the two sites. While maize, wheat, and teff are the major agriculture products, to some extent fruits and vegetables such as onions and tomato are grown by few farmers. Productivity is highly limited because of lack of access to irrigation system and shortage of rain which is the only source for growing crops. As the result, the community is suffered from food insecurity. According to the woreda administration office, out of 43 kebeles in the woreda 23 rural kebeles (including Finkilo and Bobessa) are dependent on the food relief program sponsored by the Government of Ethiopia.

15 Aluto-3

(Aluto-Bobessa)

18 Boseti Although there is a shortage of land in the kebele, majority of households produce adequate amount varieties of crops food thus the kebele is secured as far as food is concerned.

22 Tendaho-2 (Ayrobera)

The community is totally dependent on subsistence livestock. Thus food security in the woreda is seriously threatened. Thus since there is no farming practiced across the kebele, the community is under food relief assistance throughout the year.


4.5.4 Utilization of Water

For development of geothermal energy, accessibility of water is one of the crucial matters to be

confirmed. As mentioned above, water is one of the most serious challenges for nearly half of the

kebeles/sites. For example, two of the kebeles need to travel from 15 to 30 km to fetch water. Even the

sources of water that are easily accessible have not been safe. Only households from three kebeles

claimed the water they consume is safe and clean. Respondents from Meteka, Boset and Arabi reported

they accesses pipe water. However in the case of Boseti, there are times when they face scarcity of water,

particularly from January to May. Table 4.5.4 summarizes the statuses of water access in fifteen


4-24

April 2015


prospective sites.

Table 4.5.4 Statuses of Water Access in 15 Prospective Sites

Site Water source Distance

(Km) Scarcity period

Water quality For people For animals

Afar region Allalobeda (Tendaho-3) River River 0.5 - 2 - Not safe water

Dallol Pond Pond 25 – 30 All year Not safe water Danab River River - All year Not safe water Damali River River - All year Not safe water Dofan River River 0.5 - 1 - Not safe water Boina Rain/Pond Rain/Pond 15 - 20 April - June Not safe water Kone Lake Lake 0.5 - 1 - Not safe water

Meteka Borehole River 0.5 - Safe water Teo River - - - Not safe water

Ayrobera(Tendaho-2) - - - - - Oromia region

Boseti Pipe Pond 2 Jan - May Safe water Bobessa (Aluto-3) Lake/River Lake/River 7 - Not safe water Finkilo (Aluto-2) Lake/River Lake/River 7 - Not safe water

Gedemsa River River 7 Summer Not safe water Nazareth Birka River 0.5 - Safe water

Somali region Arabi Borehole River 0.5 - Safe water


4.5.5 Displacement and Resettlement

The scale of geothermal energy development project is not yet determined at present, some of the areas

within the prospective sites shall be acquired by the project proponent for implementation of the project.

Data and Information on land clam were collected through interviews at kebele lebel level in the

prospective sites.

Table 4.5.5 below addresses the possible conditions that could lead to displacement of residents before

implementation of the project.

Table 4.5.5 Displacement and Resettlement/Land claim

No. Site Current status

No. of land

owner around the site

Size of the land

owned (ha)

No. of people grazing

around the site

1 Dallol This area of the site is neither exploited for residential houses nor for, farming or grazing. However it is part of the resource for traditional salt mining.

1 1 -


Allalobeda geothermal project site is found in Dubti woreda in Gurmudela Kebele. The project site is situated 15 km away from Logia town which at 586 km from Addis Ababa. Allallobeda, is not fertile for agriculture due to shortage of rain/water, both for drinking and farming. The community depends on water redirected from Awash River. This Geothermal site is located in an area where there are no residential houses and farming plots. However, the community uses the springs for drinking their animals and grazing livestock. The Tendaho geothermal fields are at an advanced exploration stage, including deep exploratory wells. The site is specifically located within Ayirolef Kebele borders and closely located to Semera Town (9kms NE).

6 6.5 10


4-25

April 2015



No. of land


Size of the land

owned (ha)


around the site

3 Boina The site is located at the top of a mountain, very far away from human movement. Thus it is not used for grazing livestock or other related purpose.

0 - -

4 Damali Not residential area around the site - - -

5 Teo Not residential area around the site - - -

6 Danab Not residential area around the site - - -

7 Meteka

The Geothermal site is located within the village of Meteka Kebele where many residential houses and shops are built. There is also an Orthodox Church (St. Mary Church) within the site. In terms of this, therefore, there will be dislocation.

5 12 2

8 Arabi The project site is located about 4 km away from residential areas; therefore, there is no risk of demolishing huts/houses of the community. Grazing lands however could be included in the site.

3 14.5 1

9 Dofan

Dofan geothermal sites are located in the Southern part of Afar Region near Awash River and Melka Werer town. Administratively it is located in Hugub Kebele, Dulecha Woreda. There are two potential geothermal sites which are located on the mountainous caldera/cone created by the Rhyolitic volcanic centers deposition. The woreda town Dulecha is located about 27 km from the site/Dofan. Both the woreda and the kebele are situated in area where public transport is not available. The Predominant land cover types in Dofan and surrounding areas are Intensively Cultivated land, State Farm land, Open Grassland, Open Shrub Grassland and Perennial Marsh. State Farm land (Amibara Farm) and Intensively Cultivated land units are closely located to these geothermal sites. People in the Dofan site live on mainly livestock breeding and very few of them are working in the big sugar cane farms, although the majorities are minorities from different regions.

9 12 4

10 Kone Kone project site is located far from villages; the surrounding area however is used for common grazing.

6 8.5 2

11 Nazareth

There are no residential huts around this site; however the springs located in the middle of farming plots of land belong to different individual farmers. Moreover, an Orthodox Church already claimed two of the thermal pits on which the Church has built bathing rooms.

2 unknown 4

12 Gedemsa The site is located far from residential areas however it is used for grazing livestock. In addition, the site is surrounded by farming plots which belong to individual community members.

1 3 3

14 Aluto-2 (Aluto- Finkilo)

According to the National Geothermal Energy Resource survey map, there are three potential sites in Aluto area, namely Aluto Langano, Aluto Bobessa and Aluto Finkilo. Out of these, Aluto Langano geothermal prospect is under development. These geothermal sites are located south of Lake Ziway (8kms) and north of Lake Langano (9 kms). Administratively Aluto Finkilo geothermal site is located in Golba Aleto kebele and Aluto Bobessa is in Aluto Kebele (Ziway Dugda woreda, Arsi Zone, Oromia Region). Bobessa and Finkilo are located adjacent to each other. Although the actual size of the projects is not yet determined, there are a few huts within the caldera. Besides since the project area is exploited as a grazing land for the same community, unspecified size of the land will be included in the site. In general these sites are densely settled by town residents. Although the actual size of the projects is not yet known, there are few huts within the caldera. Besides since the project area is exploited as a grazing land for the same community, unspecified size of the land will be included in the site.

8 13 7

15 Aluto-3 (Aluto- Bobessa)

7 11.5 2

18 Boseti

Boseti Geothermal site is closely located to Welenchiti town (10km) to south west direction. Administratively Boseti geothermal potential site is located in Gara Dera Kebele, (Boset woreda, East Shewa Zone, Oromia Region). The site also closely located/ along border with Rukecha Boqore & Sifa Bote Kebeles. With regard to elevation,

2 4.5 1


4-26

April 2015



No. of land


Size of the land

owned (ha)


around the site

Boseti locality has comparatively high altitude, which ranges 1,250-2,650mts above sea level, while the geothermal site is located on the mountainous caldera/cone created by the Rhyolitic volcanic centers deposition, which have relatively high altitudes around 1,800-2,200 m above sea level. The Predominant land cover types in Boseti and surrounding areas are Dense Shrubland, Intensive Cultivated land, Moderately Cultivated land and Open Shrubland. Boseti geothermal site is specifically located on Dense Shrubland unit with close location with Intensively cultivated lands.

22 Tendaho-2 (Ayrobera)

Not residential area around the site - - -

Total 50

Source: ESIA Report

After the determination of the project site and the project scale, detailed land boundary should be settled

according to the land acquisition procedure of the government of Ethiopia. Site specific adverse impacts,

both on natural and social environment, are summarized in Appendix 4.4.


4-27

April 2015


4.6 Environmental Management Plan

4.6.1 Environmental Management Plan (EMP)

Environmental Management Plan (EMP) is prepared on the basis of identified impacts and their level of

significance. The objective of this EMP is to identify project specific environmental and social actions

that will be undertaken to manage impacts associated with the development and operation of the

proposed geothermal power plant. Significant impacts that are detailed in the previous section shall be

mitigated through appropriate methods and then subject to mechanisms of environmental management

plan using monitoring and auditing as instrument. Site specific environmental impacts caused by the

implementation of geothermal projects are summarized in Appendix 4.4.

The EMP is to be prepared in the process of EIA study. Detailed mitigation measures and management

plan need to be formulated after determination of the project site, along with techno-economic

feasibility studies. However, it is quite necessary to deal this issue in a comprehensive manner so as to

induce basic requirements for the upcoming project level design and full EIA studies. Table 4.6.1

summarizes the mitigation measures to be taken at the beginnings of construction phase.

Table 4.6.1 Mitigation Measures for EMP

Activities Components Potential Impacts Mitigation Measures Land acquisition Land securing Dislocation of affected

people Project office shall implement all necessary protocols for conversation of land use pattern for the project site from grazing to industrial use.

Relocation of displaced people

It will be ensured that all legal requirements are implemented with respect to Ethiopian regulations pertaining to use of land for industrial use.

Benchmarking Asset dispossession Site boundary will be marked out. It will be ensured that land taken during construction of project is restricted to pre-agreed area.

Change in life style All requisite permits will be obtained prior to project activities.

Disturbance to existing ecosystem

Disturbance to hot spring present around project area will be minimal. The streams shall be protected and preserved and natural drainage pattern shall not be disturbed.

Fencing Loss of vegetation cover Relocation site and/or compensation incentives will be in place based on Ethiopian regulation.

Change in ecology and land use pattern

Plantation of the surroundings area will start with the commencement of construction activities.

Movement of manpower, machinery and materials

Increase in traffic movement

Disturbance to community & its safety

Planning activities in consultation with local communities so that activities with the greatest potential to generate noise are planned during periods of the day resulting in minimum disturbance.

Encroachment of are for parking and construction

Contribution of dust and gaseous pollutants like SO2, NOx, CO, VOC to ambient air quality

Preventive maintenance of vehicles and machinery at regular intervals.

Contribution to ambient noise level

Advice traffic police about the activities. Traffic will be controlled by deploying local people at sensitive accident prone locations who will also oversee the movement of livestock on these roads.

Site leaning, levelling & excavation

Operation of heavy earth moving machinery & equipment

Disturbance to native vegetation and habitats

Plantation of the surroundings area will start with the commencement of construction activities.

Removal of Change in land use All equipment will be operated within specified


4-28

April 2015


Activities Components Potential Impacts Mitigation Measures vegetation at site pattern design parameters (Site preparation and construction

phases) Piling of soil Disturbance to existing

nearby land users creating visual impact

Regular monitoring of noise level and vibration level due to construction activities at site and in the local areas to conform to the standard as prescribed by most financial institutions.

Storage of oil Increase to ambient noise level

Design additional methods to support already existing business opportunities and community development.


4.6.2 Monitoring plan

Environmental monitoring plan is included in the EMP. Environmental monitoring and auditing shall be

undertaken in all phases of project activities to check that the proposed environmental management

measures are being satisfactorily implemented and that they are delivering appropriate level of

environmental performances. Here it might be necessary to emphasize that mitigation measures and

auditing plans are not developed for mere purpose of project licensing but are legally enforcing

document to be followed and performed accordingly throughout project life. A general form of

monitoring plan to be applied to the prospective sites is given in Table 4.6.2 below.

Table 4.6.2 Monitoring Plan for Geothermal Energy Development Project

Impact Method Parameters Monitoring place/location Frequency

Air quality

Measurement/Sample PM/PM10, NOx, SOx Processing stacks Half-yearly Concentration & exposure time Point source of

non-condensable gases Half-yearly

PM/PM10, CO2, Temp., Oxygen level, combustion efficiency

Combustion source Half-yearly

Noise Measurement Leq dB(A) Drilling sites Half-yearly

and upon complaints

Surface and groundwater, if any

Sampling Temp., pH, Oil, SS, COD Groundwater wells, Oil/grease traps, water separators, sedimentation tanks

Quarterly

Soil

Sampling Moisture content, pH, salinity, N, P, Cl, K, Na

Agricultural plots near and in projects sites

Annual

Heavy metals (Mn, Fe, etc.) Every three years

Domestic solid waste Audit, photographic documentation, interviews

Generation, storage, recycling, transport and disposal

Plant premises Quarterly

Biodiversity Visual inspection and photographic documentation

General condition of the floral cover

Plant and landscaped areas

Annual

Resource use

Metering Water and energy consumption Plant and surrounding areas

Continuously

Audit Raw material consumption Plant and surrounding areas

Continuously

Health and safety

Health and safety survey Proper use of PPE, presence of safety signs, firs aid kit, fire fighting devices, injury illness records, emergency exit and plans, Accident statistics recording in accordance with ILO standards.

Plant road linking plant to project site

Continuously

Socio-economic Field questionnaire Local population an Authorities Plant and surrounding

areas Annually

Interviews Employment records and Plant Continuously Nippon Koei Co., Ltd. JMC Geothermal Engineering Co., Ltd Sumiko Resources Exploration & Development Co., Ltd.

4-29

April 2015


Impact Method Parameters Monitoring place/location Frequency Worker association

Operations monitoring

Visual inspection and documentation

Production rate, gas flow rates, counter readings, pressure valves, temperatures, abnormal readings, overloads, stoppages

All facilities and major equipment at Plant area

Daily


4.7 Consultation with stakeholder

Stakeholder Consultations were implemented in the ESIA Study, namely at scoping stage, through the

interviews at communities (March –July 2014).

Stakeholder Consultation at scoping stage

Consultation with stakeholder at the prospective sites had been conducted through interview and using

questionnaires shown in section 4.3.1 (Methodology of Baseline Study) in the ESIA study. As

mentioned in section 4.3.1, hearings and questionnaire surveys had been conducted at seven Woreda

level sector offices, and more than 100 officials from different sectors were participated. The contents of

questions developed for the survey and the stakeholder consultation are summarized as follows:

Existence of any directive/guidelines in the offices relevant for establishment and resource

utilization around the proposed project areas.

Existence of development plan in or around the proposed project area.

Personal opinion of interviewee on establishment of this geothermal energy development project in

the area.

Together with above, themes of discussion developed for group discussion are as follows:

Have you heard about geothermal energy?

What are the major constrains of the community?

What potential benefits do you expect from the geothermal project?

What potential negative impacts do you expect from the geothermal project?

If there are negative effects of the project what do you recommend avoid/minimize the impacts?

Are there minority groups in the area, and what problems do they face?

Is there conflict story due to resource or other causes among the community?

If the project requires relocation of people, do you think the concerned group will agree?

In what form do you think the relocated households should/want to receive the compensation?

Any other comments

As results of the stakeholder consultations, the discussions with local people were almost same for the

prospective areas as follows:

Up to now there is no directives that prevent the geothermal energy development projects from

establishment along the proposed sites.

For the establishment of the project, necessary precautionary measures for resource utilization


4-30

April 2015


should be taken.

All of interviewed officials expressed their positive support for establishment of the geothermal

energy development projects with necessary measures.

Together with the opinion of officials above, meeting with people who had potential directly affected by

the project revealed the following opinions:

Fear of losing farm lands and inability to get lands of equivalent land conditions.

Fear of losing free large grazing land for livestock.

Fear of declining cattle population due to shortage of such grazing land elsewhere and its

implication on family income.

Fear of losing plain playground of their children.

Loss of proximity to nearby town social facilities such as big market, health center, access to

transport service, etc.

Fear of getting appropriate compensation for their assets.

In order to remove the issues and concerns of the community above, due regards and detailed

explanations were given to the community based on the legal, social and environmental land regulations

stated in the proclamation of Federal Republic of Ethiopia No. 1/1995.

Names, responsibilities and status of respondents and interviewees are listed in Appendix 4.6.

4.8 Conclusion and Recommendation

4.8.1 Conclusion

The environment and social impact assessment study on the geothermal energy development was

conducted. The study included site surveys and collection of readily available data for the prospective

sites, and IEE for scoping of potential impacts caused by the implementation of geothermal energy

development projects. The study revealed the followings:

Although implementation of geothermal energy development project will affect some

environmental and social impacts on the sites, both positive and negative, there are no prospective

sites which would be affected negative impacts seriously by the implementation of the geothermal

energy development project in terms of the environment.

According to the stakeholder consultation conducted at the prospective sites of Woreda level, all

of interviewed officials expressed their positive support for development of the geothermal

energy with necessary measures such as proper land compensation.

The stakeholder consultation also revealed that the main concern of potentially project affected

people (PAP) is fear of losing farm land, grazing land for livestock. Due regards and detailed

explanations should be made to PAPs in case the geothermal energy development projects are to

implement at some of the prospective sites.

As for the gaps between Ethiopian Legislations and JICA Guidelines (2010) for policies on


4-31

April 2015


Environmental Assessment, it can be concluded that the JICA Environmental guidelines and the

legislation in Ethiopia do not have major contradictions as well as Safeguard Polices in the World

Bank, except perhaps certain procedural adjustments during project implementation such as public

consultation and public disclosure. The studies on policy aspects in this study showed that the

projects for geothermal energy development were classified under CATEGORY I by the Ethiopian

environmental project categorization. This means that the geothermal energy development

projects are required to conduct a full EIA study complying with national standards set by the

country.

The National Energy Development Policy in Ethiopia states that; i) Equitable development of the

energy sector together with other social and economic developments, and ii) Development of

indigenous resources with minimum environmental impact and equitably distribution of

electricity in all the regions. In addition to the National Energy Development Policy mentioned

above, the National Environmental Policy also states to promote the development of renewable

energy sources and reduce the use of fossil energy resources both ensuring sustainability and for

protecting the environment, as well as for their continuation into the future.

Geothermal energy is one of the environmental sound indigenous renewable energies in Ethiopia.

Proceedings of geothermal energy development comply with the national policies of Ethiopia.

4.8.2 Recommendation

Geothermal energy development projects which have an electricity generation capacity more than 25

MW are required the implementation of full scale EIA in accordance with EIA related laws and

regulations of Ethiopia prior to the implementation of the project. As shown in section “4.2

Environmental Laws and Regulations”, EIA process consists of series of several procedural phases

starting from pre-screening consultation with EPC and submission of a screening report and ending up

by obtaining an EIA approval. The project proponent should start the EIA procedures in cooperation

with other sectoral agencies such as Ministry of Water, Irrigation and Energy (MoWIE), regional

governments, etc. For the implementation of the EIA, followings should be noted:

EIA should be conducted in accordance with the Ethiopian EIA process.

EIA should be carried out for the selected site by the project proponent according to the Ethiopian

Guidelines and/or international requirements.

After the determination of the project site(s), EIA should start prior to the test drillings, and

continuously conducted parallel to the test drilling.

The EIA report prepared based on above shall be revised considering the results of the test

drilling above. Results of ESIA survey conducted in this master plan study can be utilized for the

implementation of the EIA

Additional EIA should be conducted if necessary according to the revised EIA report.

The EIA is to be conducted considering the specific features of environmental impacts of

geothermal energy development.

EIA approval should be obtained before the application of the development right of the project.


4-32

April 2015


CHAPTER 5 Formulation of Master Plan

5.1 Target and Methodology

The master plan is formulated by first setting out the development targets (how much installed capacities

are required and when) and then by prioritizing the identified candidate projects using a multi-criteria

analysis to meet the targets set out.

5.1.1 Target of the Master Plan

Table 5.1.1 gives the development targets for this master plan. Target year is set as the same period as

in the EEP master plan. In order to make the plan more concrete, the master plan period is divided into

three terms, namely: short, medium, and long. First, the committed and ongoing projects are expected

to be completed in the short term. Secondly, high priority prospects aim to develop around 500 MW in

the exact same way as in the EEP generating plan. And last, a total of 5,000 MW of geothermal power

is expected to be developed in the long term in Ethiopia.

Table 5.1.1 Development Target of the Master Plan

Item Target Remarks

Period

2015–2037 (23 years) Short term: 2015-2018 (4 years) Medium term: 2019-2025 (7 years) Long term: 2026-2037 (12 years)

EEP MP: 2013–2037 (25 years) Wind and Solar MP: 2011–2020 (10 years)

Installed Capacity Short term 700 MW Committed and ongoing sites Medium term 1,200 MW Same target as EEP MP Long term 5,000 MW Same target as EEP MP

MP: Master Plan Source: JICA Project Team

5.1.2 Methodology of the Master Plan

This master plan is formulated by prioritizing the 22 geothermal prospects identified based on the

results of various kinds of geological survey and collected data from past surveys, using multi-criteria

analysis. The multi-criteria analysis is the method of prioritizing the candidate projects by screening

and ranking them using multiple criteria as shown in Figure 5.1.1. Five criteria are used: (i)

development status, (ii) environmental risks, (iii) geothermal potential, (iv) economics, and (v) site

specific factors. First, depending on the development status and commitment of the donors, the

committed prospects are prioritized by giving them a high rank. In the following screening, the

prospect which has severe adverse environmental impact, for example those located in the national

park, is given low priority. Other sites are ranked based on economics estimated using geothermal

potential, installed capacity, drilling well, plant cost, and other required facilities. And finally, taking

into consideration site specific factors such as other socio-environmental impacts, minor arrangement

of the ranking is discussed.


5-1

April 2015



Figure 5.1.1 Flow of Multi-Criteria Analysis

5.2 Multi-Criteria Analysis for Prioritizing the Geological Prospects

5.2.1 Factors to be Considered

(1) Development Status

In general, with the progress of the development status, the reliability of the geothermal resource is

increased. Using the Australian Geothermal Reporting Code Committee 1 classification, the

development status and geothermal reliability of the 22 geothermal prospects are evaluated and

categorized into three sections, namely: 1) measured, 2) indicated, and 3) inferred geothermal

resource.

Table 5.2.1 shows the development status of the 22 geothermal prospects. Aluto-1 (Aluto-Langano)

and Tendaho-1 (Dubti), where some test drillings were already done, are evaluated as measured and

1 Global Review of Geothermal Reporting Terminology, Feb. 2013, Hot Dry Rocks Pty Ltd

Screening-1Development Status

Start

Ranking-1Geothermal Knowledge and Potential

Screening-2Environmental and Social Impact(National Park)

The sites which are at advanced development stage and donor involvement are given high priority.

Ranking-2Project Economics

Ranking-3Site Specific Factor

Prioritizationof 22 Geothermal Prospects

The sites which have high potential and high reliability are given high priority.

The sites which have high economics (lower generation cost and higher EIRR) are given high priority.

The sites which have advantages in terms of environmental/social impacts, required grid, accessibility to the site, security situation, direct thermal use and regional demand, etc. are given high/low priority.

The sites which have immitigable adverse environmental risks/impacts such as locating in national parks are given low priority.


5-2 April 2015


indicated resource, respectively. Other sites where any detailed exploration surveys have yet to be

done are evaluated as inferred resource.

Table 5.2.1 Development Status and Geothermal Resource

Site Temperature

Class Geothermal Resource

Inferred Indicated Measured 1 Dallol B 44 N/A N/A 2 Tendaho-3 (Allalobeda) A 120 N/A N/A 3 Boina C 100 N/A N/A 4 Damali C 230 N/A N/A 5 Teo B 9 N/A N/A 6 Danab B 11 N/A N/A 7 Meteka B 130 N/A N/A 8 Arabi C 7 N/A N/A 9 Dofan B 86 N/A N/A 10 Kone D 14 N/A N/A 11 Nazareth C 33 N/A N/A 12 Gedemsa D 37 N/A N/A 13 Tulu Moya C 390 N/A N/A 14 Aluto-2 (Finkilo) A 110 N/A N/A 15 Aluto-3 (Bobesa ) A 50 N/A N/A 16 Abaya B 790 N/A N/A 17 Fantale C 120 N/A N/A 18 Boseti B 265 N/A N/A 19 Corbetti B 1000*1 N/A N/A 20 Aluto-1 (Aluto-Langano) A 16 70*2 5 21 Tendaho-1 (Dubti) A 280 10*3 N/A 22 Tendaho-2 (Ayro Beda) A 180 N/A N/A

N/A: Not available *1 Reykjavík Geothermal *2 Study on Geothermal Power Development Project in the Aluto Langano Field, Ethiopia, METI (Japan), 2010, *3 Consultancy Services for Tendaho Geothermal Resources Development feasibility Study, ELC, 2013


(2) Socio-environmental Impact

According to the environmental and social consideration study mentioned in Chapter 4, Fantale

geothermal prospect is located around the Awash National Park and it is expected that it will be

difficult to develop. Therefore, Fantale prospect is given a low priority in the ranking. With the

exception of Fantale prospect, the 21 other geothermal sites do not encroach on the range of the

national park and do not have immitigable adverse environmental risks and impacts.

(3) Geothermal Potential

Based on the various geological surveys carried out in this study, geothermal potential of each site is

assessed and discussed in Chapter 3. The result of the reservoir assessment is summarized in Table

5.2.1. As per the electrical development plan mentioned in Chapter 2, the electrical demand is

forecasted to increase much higher than the sum of hydropower and geothermal potential in the early

2030s. Therefore, EEP requests the development of the maximum possible geothermal potential. In

this study, the installed capacity of each power plant is set as equal to the geothermal potential in each

prospect.


5-3

April 2015


As mentioned in Section 2.4, several donors have started development and drilling surveys of some of

the prospects, such as Corbetti, Aluto-1 (Aluto-Langano), and Tendaho-1 (Dubti). The inferred

potential of Corbetti geothermal prospect is estimated at 1000 MW referring to publicly available

information from Reykjavík Geothermal (RG). Similarly, the indicated and measured potential of

Aluto-1 (Aluto-Langano) and Tendaho-1 (Dubti) were taken from the existing simulation studies.

The reservoir temperature of Kone and Gedemsa prospects are assumed to be very low (100~170 °C

based on the geochemical analysis) that those prospects cannot use flash-type generation but only

binary-type generation. Therefore, plant construction cost of Kone and Gedemsa prospects are

expected to be higher than any other prospects with Class A and B reservoir temperatures.

(4) Economics of Candidate Plants

The project economics are measured by two indicators: (i) generation cost and (ii) economic viability.

1) Cost of Electricity Generation

To compare the competing power plants (geothermal, hydropower and other plant types), the

electricity generation costs (cost of generation) per kWh are calculated. Here the generation cost is

defined as the sum of annualized capital cost and annual O&M cost of power plants, divided by the

annual power production (kWh). The capital costs are annualized using a discount rate (social

opportunity cost of capital) of 10% for the economic life. All the costs are expressed in 2012 price.

The capital cost consists of direct costs (preparatory work, well drilling, fluid collection and

reinjection system (FCRS), and power plant construction), indirect cost, and interest during

construction (IDC).

The direct costs except for geothermal power plant are estimated from past results and plans provided

by EEP. The economic life and plant factor of each power plant used for the calculation of capital

recovery factor and electricity production are shown in the tables below. The economic life of

geothermal power plants is adopted from the worldwide standard of “30 years”, and that of

non-geothermal power plants is taken from the adopted value in the EEP master plan study.

Plant factor of geothermal power plants is taken as “90%”, adopted from standard geothermal power

plants, and that of wind farms is taken from the past records of Adama and Ashegoda wind farms,

while those for hydropower and other power plants are taken from the planned value in EEP master

plan.


5-4

April 2015


Table 5.2.2 Economic Life

Plant Type Economic Life Time

(years) Geothermal 30 Hydropower 75 Wind 20 Solar 40 Energy from Waste 30 Biomass 25 Diesel 20 Gas Turbine 20 CCGT 25


Table 5.2.3 Plant Factor

Plant Type Plant Factor

(%) Geothermal 90.0 Hydropower 20.0 ~92.0 Wind 26.4 ~33.6 Solar 20.0 Energy from Waste 84.9 Biomass 23.9~27.5 Diesel 84.0 Gas Turbine 90.0 CCGT 87.5


Table 5.2.4 gives the costs generation by the candidate hydropower plants which are calculated based

on the basic data given by EEP. The generation costs of the candidate hydropower plants vary from

US$0.02-0.15/kWh. Most of the candidate hydropower plants have more than 100 MW of installed

capacity and are comparatively economical.

Table 5.2.4 Generation Costs of Candidate Hydropower Plants

Source: JICA Project Team (Data of candidate plants was given by EEP)

Table 5.2.5 presents the generation costs of other renewable energy and thermal power plants. The

costs of Adama I and Ashegoda II wind farms are lowest and estimated at US$0.084-0.090/kWh.

Following these, Bazma Biomass Power Plant has a lower generation cost. Except for the wind farm

above, generation costs of all plants exceed US$0.10/kWh and are less economical than most of the

candidate hydropower plants.

RankingOrder

CandidateHydropower Plant

InstalledCapacity

(MW)

PlantFactor

(%)

EnergyProduction(GWh/year)

ConstructionCost

(mil $)

IDC Cost(mil $)

Total Cost(mil $)

AnnualizedCapital Cost(mil $/year)

O&M Cost(mil $/year)

AnnualizedCost

(mil $/year)


1 Beko Abo 935 81% 6632 1260.8 441.3 1702.1 126.18 12.6 138.79 0.02092 Genji 216 49% 910 197.6 69.1 266.7 19.78 2.0 21.75 0.02393 Upper Mendaya 1,700 58% 8582 2436.4 852.7 3289.1 243.83 24.4 268.20 0.03124 Karadobi 1,600 60% 7857 2576.0 901.6 3477.6 257.80 25.8 283.56 0.03615 Geba I + Geba II 372 57% 1709 572.0 200.2 772.2 57.25 5.7 62.97 0.03686 Genale VI 246 74% 1532 587.9 205.8 793.7 58.84 5.9 64.72 0.04227 Gibe IV 1,472 50% 6146 2588.3 776.5 3364.8 259.03 25.9 284.92 0.04648 Upper Dabus 326 51% 1460 628.2 219.9 848.1 62.87 6.3 69.15 0.0474

11 Sor II 5 92% 39 18.6 3.7 22.3 1.86 0.2 2.05 0.053210 Birbir R 467 70% 2724 1231.1 369.3 1600.4 123.21 12.3 135.52 0.04979 Halele + Werabesa 436 54% 1973 886.0 310.1 1196.1 88.67 8.9 97.53 0.0494

12 Yeda I + Yeda II 280 45% 1089 540.2 189.1 729.3 54.06 5.4 59.46 0.054613 Genale V 100 66% 575 297.7 89.3 387.0 29.79 3.0 32.77 0.057014 Gibe V 660 36% 1905 1036.9 311.1 1348.0 103.77 10.4 114.14 0.059915 Baro I + Baro II 645 46% 2614 1595.9 558.6 2154.5 159.72 16.0 175.67 0.067217 Lower Didessa 550 20% 976 619.2 185.8 805.0 61.97 6.2 68.16 0.069916 Tekeze II 450 69% 2721 1690.4 591.6 2282.0 169.17 16.9 186.08 0.068418 Gojeb 150 48% 562 526.8 184.4 711.2 52.72 5.3 57.99 0.103219 Aleltu East 189 53% 804 760.6 266.2 1026.8 76.12 7.6 83.73 0.104120 Tams 1,000 69% 6057 5814.9 2035.2 7850.1 581.95 58.1 640.10 0.105722 Abu Samuel 6 30% 16 18.5 2.8 21.3 1.85 0.2 2.04 0.129721 Aleltu West 265 46% 1067 1180.5 413.2 1593.7 118.14 11.8 129.95 0.121823 Wabi Shebele 88 91% 691 887.8 221.9 1109.7 88.85 8.9 97.73 0.141424 Lower Dabus 250 29% 637 866.3 259.9 1126.2 86.70 8.7 95.36 0.1497


5-5

April 2015


Table 5.2.5 Generation Costs of Non-Hydro and Non-Geothermal Plants

Source: JICA Project Team (Data of each power was given by EEP)

The construction cost of geothermal power plants mainly consists of well drilling, FCRS, and power

plant construction. Power plant construction and FCRS are estimated depending on the planned

installed capacity, while the cost of well drilling is estimated based on target well depth in resource

development, steam and brine flow per production well and the characteristics (depth and temperature)

of the geothermal reservoir, taking into consideration geothermal models and characteristics of each

prospect mentioned in Chapter 3. Regarding Aluto-1 and Corbetti, their construction costs are taken

from the outgivings based on a more detailed study conducted in the past.

The JICA Project Team conducted well simulation to determine the relation between reservoir

temperature and steam and brine flow per production, setting depth, pressure, and permeability of

geothermal reservoir. Well drilling cost is estimated based on the simulation result and well depth

based on previous survey results. Figure 5.2.1 presents the relation between reservoir temperature and

power output converted from flow rate. Although it differs largely depending on the permeability, the

result suggests higher reservoir temperature has a larger amount of steam and brine flow and bigger

power output per production well.


Figure 5.2.1 Well Simulation Results

Plant Type Candidate PlantInstalledCapacity

(MW)

PlantFactor

(%)


ConstructionCost

(mil $)

IDC Cost(mil $)

Total Cost(mil $)


O&M Cost(mil $/year)

AnnualizedCost

(mil $/year)


Wind Farm Adama-I 51.0 33.6% 150 96.9 9.7 106.6 11.38 1.3 12.66 0.0844Wind Farm Adama-II 30.0 26.6% 70 57.0 5.7 62.7 6.70 0.8 7.45 0.1064Wind Farm Ashegoda-I 90.0 26.4% 208 171.0 17.1 188.1 20.09 2.3 22.34 0.1074Wind Farm Ashegoda-II 153.0 31.6% 424 290.7 29.1 319.8 34.15 3.8 37.97 0.0896Solar EEPco MP 300.0 20.0% 526 540.0 54.0 594.0 55.22 7.5 62.72 0.1192Energy from Waste EEPco MP 25.0 84.9% 186 144.0 7.2 151.2 15.28 32.1 47.35 0.2545Biomass Bazma 120.0 27.5% 289 183.7 9.2 192.8 20.23 11.1 31.30 0.1083Biomass Meikasedi 138.0 23.9% 289 203.4 10.2 213.6 22.41 12.4 34.83 0.1205Diesel (HFO) EEPco MP 70.0 84.0% 515 144.2 14.4 158.6 15.89 92.7 108.59 0.2108Gas Turbine EEPco MP 140.0 90.0% 1104 70.0 10.5 80.5 8.22 140.2 148.43 0.1344CCGT EEPco MP 420.0 87.5% 3219 525.0 78.8 603.8 57.84 292.9 350.77 0.1090

0.0

2.0

4.0

6.0

8.0

10.0

12.0

14.0

16.0

18.0

20.0

160 180 200 220 240 260 280 300 320

Pow

er o

utpu

t (M

W)

Reservoir Temperature (℃)

kh=0.5 darcy-m

kh=2 darcy-m

kh=5 darcy-m

Class A

Class B

Class C


5-6 April 2015


The success rate of well drilling is also assumed to be 80% for the Aluto and Tendaho (Dubti and

Ayrobera) area, where a study on depth and scale of geothermal reservoir was done, and 70% for the

other sites at the initial stage. Based on the productivity of one production well and the success rate,

the necessary number of production and reinjection wells is calculated. The diameter of production

well is uniformly set at 8.5 inches at the bottom of the well which is the standard and applied in the

past in Ethiopia. The drilling cost is given by multiplying the unit cost (US$1,750/m) which is

determined with worldwide standard price 2 assuming fully contracting out. In case that GSE

implements the drilling by his own rigs and equipments, the drilling cost is assumed to lower around

US$1,500/m. In this case, the generation costs also come down with about US$0.003-0.013/kWh as

shown in Table 5.2.6.

The power plant construction cost including FCRS is calculated assuming a 3-year construction period

within the total development period of six years similar to the implementation plan shown in Section

5.3 and in reference to the model case of 70 MW power plants, which costs US$14 million in EEP

master plan.

Table 5.2.6 shows the generation cost of the geothermal plants. As mentioned above, Kone and

Gedemsa, which are assumed to have low reservoir temperatures, can use only binary-type generation.

Therefore, they are excluded from the calculation of generation cost for flash-type geothermal power

plants. As a result of the estimation, the generation costs in Aluto and Tendaho area, which are

assumed to have high reservoir temperatures, are US$0.05-0.06/kWh and the lowest for all prospects.

Corbetti, where RG already holds the license, is also US$0.059/kWh and more economical. Following

them, Abaya, Boseti and Meteka, with large geothermal potential, are estimated to be US$0.07/kWh

and economical. On the other hand, although Teo, Dallol, and Danab are assumed to have Class-B

reservoir temperature, their generation costs are estimated to be more than US$0.10/kWh and less

economical. It is caused by large cost for access as it was impossible for the JICA Project Team to

conduct the site survey. The generation costs of Tulu Moye, Fantale, Nazareth, Damali, Boina, and

Arabi, which are assumed to have Class-C reservoir temperature, are very high because of necessary

large number of well and estimated more than US$0.10/kWh and less economical.

2 Geothermal Handbook: Planning and Financing power generation, Energy Sector Management Assistance Program, World Bank, June 2012


5-7

April 2015


Table 5.2.6 Generation Costs of Geothermal Power Plants


To sum up the estimation of generation cost, the rank order of the geothermal prospects is summarized

Table 5.2.7. Among 22 prospects, Aluto and Tendaho area are ranked highest except for Corbetti

where RG has development license, and followed by Abaya. In addition to Aluto and Tendaho area,

Boseti and Meteka, located between Aluto and Tendaho in the Great Rift Valley, are also ranked high.

Table 5.2.7 Ranking Order of the Geothermal Prospects


In this master plan study, geothermal potential, which was not done in EEP master plan, has been

assessed. In the comparison between the generation cost of hydropower and other plant types and that

of geothermal based on the geothermal potential, the revised development prioritization of all plant

types is proposed.

Figure 5.2.2 and Figure 5.2.3 compares the generation costs of geothermal and hydropower, and

RankingOrder


(MW)

PlantFactor

(%)


ConstructionCost

(mil $)

IDC Cost(mil $)

Total Cost(mil $)


O&MCost

(mil $/year)

AnnualizedCost

(mil $/year)


Cost of GenarationDrilled by GSE

($/kWh)15 Dallol 44 90 346.9 321.5 48.2 369.7 34.10 3.2 37.32 0.1076 0.10196 Tendaho-3 (Allalobeda) 120 90 946.1 506.4 76.0 582.3 53.72 5.1 58.78 0.0621 0.0584

18 Boina 100 90 788.4 754.7 113.2 867.9 80.06 7.5 87.60 0.1111 0.110716 Damali 230 90 1,813.3 1,693.1 254.0 1,947.1 179.61 16.9 196.54 0.1084 0.105613 Teo 9 90 71.0 63.6 9.5 73.1 6.74 0.6 7.38 0.1040 0.097119 Danab 11 90 86.7 127.0 19.1 146.1 13.47 1.3 14.74 0.1700 0.164310 Meteka 130 90 1,024.9 645.3 96.8 742.1 68.45 6.5 74.90 0.0731 0.067420 Arabi 7 90 55.2 89.0 13.3 102.3 9.44 0.9 10.33 0.1872 0.320011 Dofan 86 90 678.0 457.4 68.6 526.0 48.52 4.6 53.09 0.0783 0.0726- Kone 14 90 110.4 - - - - - - -

17 Nazareth 33 90 260.2 244.5 36.7 281.2 25.94 2.4 28.38 0.1091 0.1051- Gedemsa 37 90 291.7 - - - - - - -

12 Tulu Moye 390 90 3,074.8 2,748.0 412.2 3,160.2 291.51 27.5 318.99 0.1037 0.09462 Aluto-2 (Finkilo) 110 90 867.2 437.0 65.6 502.6 46.36 4.4 50.73 0.0585 0.05494 Aluto-3 (Bobesa) 50 90 394.2 201.1 30.2 231.3 21.34 2.0 23.35 0.0592 0.05568 Abaya 790 90 6,228.4 3,849.1 577.4 4,426.4 408.31 38.5 446.80 0.0717 0.0663

14 Fantale 120 90 946.1 855.4 128.3 983.7 90.74 8.6 99.30 0.1050 0.09999 Boseti 265 90 2,089.3 1,298.1 194.7 1,492.9 137.71 13.0 150.69 0.0721 0.06653 Corbetti 1000 90 7,884.0 4,000.0 600.0 4,600.0 424.32 40.0 464.32 0.0589 0.05897 Aluto-1 (Langano) 75 90 591.3 356.7 53.5 410.2 37.84 3.6 41.41 0.0700 0.07001 Tendaho-1(Dubti) 290 90 2,286.4 1,126.6 169.0 1,295.6 119.51 11.3 130.78 0.0572 0.0538

5 Tendaho-2 (Ayrobera) 180 90 1,419.1 725.0 108.7 833.7 76.90 7.2 84.15 0.0593 0.0570

RankingOrder

Geothermal SiteTemp.Class

InstalledCapacity

(MW)

Cost of Genaration

($/kWh)Remarks

1 Tendaho-1(Dubti) A 290 0.0572 Shallow reservoir is committed.2 Aluto-2 (Finkilo) A 110 0.05853 Corbetti B 1,000 0.0589 Committed site4 Aluto-3 (Bobesa) A 50 0.05925 Tendaho-2 (Ayrobera) A 180 0.05936 Tendaho-3 (Allalobeda) A 120 0.0621 Committed site7 Aluto-1 (Langano) A 75 0.0700 Committed site8 Abaya B 790 0.07179 Boseti B 265 0.0721

10 Meteka B 130 0.073111 Dofan B 86 0.0783

12 Tulu Moye C 390 0.1037

13 Teo B 9 0.104014 Fantale C 120 0.105015 Dallol B 44 0.107616 Damali C 230 0.108417 Nazareth C 33 0.109118 Boina C 100 0.1111

19 Danab B 11 0.1700

20 Arabi C 7 0.1872- Gedemsa D 37 - Low temperature- Kone D 14 - Low temperature


5-8

April 2015


geothermal and other power plants respectively. Generally, the generation cost of hydropower is lower

than that of geothermal power plants. However, some geothermal power plants are much more

competitive and are more reasonable than some candidate hydropower plants with similar capacity.

Prospects in Aluto and Tendaho area and Corbetti, with generation cost of around US$0.05-0.07/kWh,

are as competitive as the most economical candidate hydropower plants. Abaya, Boseti, Meteka, and

Dofan, whose generation costs are around US$0.07-0.08/kWh are also competitive and just above the

range of reasonable hydropower plants.

In comparison with other renewable energy and thermal power plants, even Adama and Ashegoda

wind farms, which are the most reasonable and exceeds US$0.08/kWh, they are not competitive

compared with the geothermal prospects ranked No.1 to No.11 in Table 5.2.7. Therefore, from the

point of view of least cost generation, geothermal must be prioritized over wind and solar in Ethiopia.

As mentioned in section 2.3.4, wind and solar power is unreliable which is influenced by climate and

weather conditions. Meanwhile, geothermal resource provides reliable electrical supply as base load.

Moreover, the Ethiopia’s energy sector is overly depending on hydropower, which is exposed to

drought risk. To reduce risk of drought, the geothermal resources should be exploited as much as

possible. This will improve Ethiopia’s energy mix, where the base load could be supported by

geothermal energy and the peak load by hydropower. .

The geothermal prospects with generation cost of US$0.10/kWh are almost equal to wind and solar

and more economical than gas turbine and diesel. The diesel generation and waste from energy are

much more expensive than the geothermal prospects.


Figure 5.2.2 Generation Cost of Geothermal and Hydropower Plants

0.0000

0.0500

0.1000

0.1500

0.2000

0 100 200 300 400 500 600 700 800 900 1000

Cos

t of G

ener

atio

n (

$/kW

h)

Geothermal Site CandidateHydropower Plant


Aluto-Langano

Abaya

Corbetti

MetekaBoseti

Tulu Moye

Dubti

Damali

Allalobeda

FinkiloAyrobera

Bobesa

Dofan

Boina

Teo

Danab

Arabi


5-9

April 2015



Figure 5.2.3 Generation Cost of Geothermal and Other Power Plants

If the Government of Ethiopia adopts preferential policy such as advantageous interest rate to promote

geothermal development, geothermal is expected to become more competitive. In this master plan,

based on the comparison of the generation cost of plant type, generation plan of geothermal power

plants is proposed to the EEP master plan which has a rough plan for geothermal development.

2) Economic Viability

The economic viability of a geothermal plant is evaluated using the economic internal rate of return

(EIRR). The EIRR is obtained by cost/benefit analysis using the cost of the geothermal plant as the

cost and the cost of the alternative plant (diesel plant) as the benefit. The EIRR is a discount rate at

which the present values of the streams of the cost and benefit are equal. The calculated EIRR is

compared with the social opportunity cost of capital taken at 10%. The project is economically

feasible if the EIRR is 10% or more.

The basic assumptions used for calculating the cost and benefit of the Tendaho-2 (Ayrobera)

geothermal plant as an example are summarized as follows:

0.0000

0.0500

0.1000

0.1500

0.2000

0.2500

0.3000

0 100 200 300 400 500 600 700 800 900 1000

Cos

t of G

ener

atio

n (

$/kW

h)




Biomass Gas Turbine

Diesel (HFO) CCGT

Aluto-Langano

Abaya

Corbetti

Meteka Boseti

Tulu Moye

Dubti

Damali

Allalobeda

Finkilo Ayrobera

Bobesa

DofanWind-Ashegoda

Wind-AdamaSolar

Energy from Waste

CCGT

Diesel (HFO)

Gas Turbine

Boina

Teo

Danab

Arabi


5-10

April 2015


Table 5.2.8 Basic Assumptions Used for Economic Evaluation of Tendaho-2 (Ayrobera)

Geothermal Plant (Cost) Alternative Diesel Plant (Benefit)

Installed capacity: 180 MW Plant factor: 90% Station use: 9% Economic life: 30 years Generated energy: 1,419.1 GWh Sales energy: 1,291.4 GWh Construction cost: US$725.0 million (2012 price) O&M cost: US$7.2 million/year (2012 price)

Installed capacity: 229 MW Plant factor: 67% Station use: 4% Economic life: 15 years Generated energy: 1,345.2 GWh Sales energy: 1,291.4 GWh Unit construction cost: US$800/kW (2012 price) Construction cost: US$183.4 million (2012 price) Fuel cost: US$0.171/kWh (2012 price) O&M cost: US$ 0.009/kWh (2012 price)


The cost/benefit streams for the top five ranked plants (Tendaho-1, Aluto-2, Tendaho-2, Aluto-3, and

Tendaho-3) are appended.

The EIRRs are given in Table 5.2.9 (ranking of geothermal power plants). Out of 18 projects, 16 are

economically viable since the EIRRs are more than the hurdle rate of 10%. Two projects (Danab and

Arabi) are not economically viable as the EIRRs are below the hurdle rate. As seen from the table, the

costs of energy and the EIRRs are perfectly correlated: the lower the cost of energy, the higher the

EIRR.

Table 5.2.9 Ranking of Geothermal Power Plants and EIRR


RankingOrder


(MW)


EIRR(%)

1 Tendaho-1(Dubti) 290 0.0572 31.7%

2 Aluto-2 (Finkilo) 110 0.0585 31.1%

3 Corbetti 1,000 0.0589 -

4 Aluto-3 (Bobesa) 50 0.0592 30.7%

5 Tendaho-2 (Ayrobera) 180 0.0593 30.8%

6 Tendaho-3 (Allalobeda) 95 0.0621 29.1%

7 Aluto-1 (Langano) 75 0.0700 -

8 Abaya 790 0.0717 25.2%

9 Boseti 265 0.0721 25.0%

10 Meteka 130 0.0731 24.7%

11 Dofan 86 0.0783 23.1%

12 Tulu Moye 390 0.1037 17.0%

13 Teo 9 0.1040 17.4%

14 Fantale 120 0.1050 16.7%

15 Dallol 44 0.1076 16.6%

16 Damali 230 0.1084 16.2%

17 Nazareth 33 0.1091 16.2%

18 Boina 100 0.1111 15.8%

19 Danab 11 0.1700 9.9%

20 Arabi 7 0.1872 8.7%

- Gedemsa 37 - -

- Kone 14 - -


5-11

April 2015


3) Site Specific Factors

i) Socio-environmental Impact

Social and environmental impact, except for national park, is taken into consideration for the

prioritization.

Environmental and social consideration study was conducted in this study. In the study, and also

when the JICA Project Team visited and surveyed the site, it was determined that there may be a

potential conflict with local people in the Dofan prospect. Therefore, Dofan is adjusted to be

ranked below the level of the economy group.

ii) Accessibility to the National Grid

The required length of transmission line from the geothermal aspects to existing national

grid/substation is measured after verification of the exact geothermal manifestation by site survey

in this study. Table 5.2.10 shows the length and voltage of the required transmission line and

substation which was examined based on the geothermal potential and installed capacity.

The extension of the national grid is to be implemented by EEP; therefore, the cost of the

extension is not included in the project cost estimated above. Taking into account the accessibility

to the national grid, the prioritization of the geothermal sites is reassessed. However, except for

prospects such as Boina, Damali, and Danab, which are located in remote areas, most of the

prospects have existing transmission lines and substations within 30 km from the site. In

comparison with the construction cost of the geothermal plant, the estimated cost of transmission

line is so small that it is not necessary to adjust the prioritization order.

Table 5.2.10 Required Length and Voltage of Transmission Line


iii) Accessibility to the Sites

Similar to the accessibility to the national grid, required access road to the site is measured after

Exsting TL(kV)

Connected Sub-stationVoltage

(kV)TL

(km)Cost

(mil $)1 Dallol 132 Wukro 132 90 23.42 Tendaho-3 (AllaloBeda) 230 Semera 230 15 5.63 Boina 230 Alamata 230 90 33.34 Damali 230 Semera 230 84 31.15 Teo 230 Semera 230 68 25.26 Danab 230 Semera 230 81 30.07 Meteka 66 Amibara 66 95 13.88 Arabi 230 Jijiga 230 65 24.19 Dofan 66 Amibara 66 7 1.010 Kone 132 Metehara 132 27 7.011 Nazareth 132 Nazareth 132 8 2.112 Gedemsa 230 Koka 230 12 4.413 Tulu Moye 132 Assela 132 30 7.814 Aluto-2 (Finkilo) 132 Adami Tulu 132 10 2.615 Aluto-3 (Bobesa) 132 Adami Tulu 132 13 3.416 Abaya 132 Sodo 400 35 19.317 Fantale 132 Metehara 132 8 2.118 Boseti 132 Nazareth 132 33 8.619 Corbetti 132 Shashamene 132 22 5.720 Aluto-1 (Langano) 132 Adami Tulu 132 14 3.621 Tendaho-1(Dubti) 230 Semera 230 11 4.122 Tendaho-2 (Ayrobera) 230 Semera 230 15 5.6

Geothermal Sites


5-12

April 2015


site survey in this study, as shown in Table 5.2.11. Taking into consideration the topography along

the access road as well as for security measures, cost of civil works for the access road and

earthworks in the site is estimated as preparatory work in the construction cost mentioned above.

Because the poor accessibility reflects the generation cost, prospects located in remote areas such

as Damali and Danab are evaluated low in the rank order of the generation cost.

Table 5.2.11 Required Length and Topography of Access Road


5.2.2 Prioritization of the Geothermal Prospects

To sum up the prioritization of geothermal prospects using multi-criteria analysis mentioned above,

the prioritization order is summarized as shown in Table 5.2.12.

Accessibility TopographyRequired Access

Road (km)Cost

(mil $)1 Dallol Accessible Rolling 7 3.52 Tendaho-3 (Allalobeda) Good Plane 12 6.03 Boina Inaccessible Mountainous 40 40.04 Damali Difficult Rolling 81 64.55 Teo Difficult Mountainous 12 12.06 Danab Difficult Rolling 80 64.27 Meteka Good Plane 3 1.38 Arabi Difficult Rolling 35 28.09 Dofan Difficult Rolling 35 28.010 Kone Good Plane 4 2.111 Nazareth Good Plane 2 0.812 Gedemsa Accessible Plane 19 9.413 Tulu Moye Accessible Rolling 12 6.014 Aluto-2 (Finkilo) Good Plane 1 0.515 Aluto-3 (Bobesa) Good Rolling 2 1.016 Abaya Good Plane 30 15.017 Fantale Accessible Rolling 16 7.818 Boseti Good Rolling 9 4.619 Corbetti Good Rolling 10 5.120 Aluto-1 (Langano) Good Plane 0 0.021 Tendaho-1(Dubti) Good Plane 10 4.922 Tendaho-2 (Ayrobera) Good Plane 7 3.3

Geothermal Sites


5-13

April 2015


Table 5.2.12 Prioritization Order of the Geothermal Prospects


Priority S: Committed Sites

Four projects, the 25 MW Tendaho-3 (Allalobeda), Corbetti, Aluto 1 (Aluto-Langano), and the 10 MW

shallow reservoir Tendaho-1 (Dubti), which were already committed by several donors, are prioritized

over other sites and are expected to go forward on their schedule.

Priority-A: Very High Economy

Five prospects, the Tendaho-1 (Dubti), Aluto-2 (Finkilo), Aluto-3 (Bobesa), Tendaho-2 (Ayrobera),

and Tendaho-3 (Allalobeda), which are assumed to have high temperature geothermal reservoirs and

an estimated generation cost of US$0.05-0.06/kWh, are evaluated as next highest priority. Aluto and

Tendaho in Priority-A is the most promising and can be prioritized over some of the candidate

hydropower projects.

Since Tendaho-1 (Dubti) and Tendaho-3 (Allalobeda) have preceded the project above, an expansion

project will be planned to develop the remaining geothermal potential in those sites. Several donors

have also planned and conducted geophysical sounding and drilling surveys in those Priority-A sites.

In this study, the JICA Project Team conducted magnetotelluric (MT) survey in Tendaho-2 (Ayrobera).

RankingOrder

Geothermal SiteInstalled Capacity

(MW)

Priority-S: Committed Project COD Donor

S Tendaho-3 (Allalobeda ) 25 2017 WBS Corbetti 500 2018 RGS Aluto-1 (Langano) 70 2018 Japan/WB

S Tendaho-1 (Dubti)-Shallow reservoir 10 2018 AFD

Priority-A: Very High Economy Energy Cost (US$/kWh)

1 Tendaho-1 (Dubti)-Deep reservoir 280 0.0572 Deep reservoir

2 Aluto-2 (Finkilo) 110 0.05853 Aluto-3 (Bobesa) 50 0.05924 Tendaho-2 (Ayrobera) 180 0.05935 Tendaho-3 (Allalobeda) 95 0.0621 Expantion

Priority-B: High Economy Energy Cost (US$/kWh)

6 Abaya 790 0.0717 RG has license7 Boseti 265 0.07218 Meteka 130 0.0731

Priority-C: Low Economy Energy Cost (US$/kWh)

9 Tulu Moye 156 0.1037 RG has license10 Teo 9 0.104011 Damali 92 0.108412 Nazareth 13.2 0.109113 Boina 40 0.111114 Dofan 86 0.0783 Conflict with residents15 Dallol 44 0.1076 Difficult due to low pH

Priority-D: Less Feasible Energy Cost (US$/kWh)

16 Danab 11 0.1700 Poor access17 Arabi 2.8 0.1872 Poor accessD Gedemsa 37 - Low temperatureD Kone 14 - Low temperatureD Fantale 48 - Overlapped with national park

Remarks


5-14

April 2015


Priority-B: High Economy

Three prospects, i.e., Abaya, Boseti, and Meteka, which are assumed to have 210-260 °C reservoir

temperature and an estimated generation cost of US$0.07-0.08/kWh, are categorized as Priority-B.

Priority-B has less economic value than Priority-A geothermal prospects and some competitive

hydropower plants, but is still more competitive than other renewable energy and thermal power

plants.

Abaya has already been licensed by RG. However, development action has yet to be done so far. In

addition to Tendaho-2 (Ayrobera), the JICA Project Team conducted MT/transient electromagnetic

(TEM) survey in Boseti prospect in this study and the result is explained in the next chapter. In Meteka,

no geophysical or drilling survey has been done as of this moment.

Priority-C: Low Economy

Following Priority-B, prospects with US$0.10-0.11/kWh generation cost such as Tulu Moye, Teo,

Damali, Nazareth, Boina and Dallol are ranked Priority-C. Dofan’s estimated generation cost is

US$0.0783/kWh and does not have any serious adverse social impact. However, there is a potential

conflict with local people. This is the reason why it is ranked lower in the group. Geothermal fluid in

Dallol is highly acidic that geothermal power development is expected to be difficult because the

materials and pipes that will be used should be resistant to strong acid corrosion. This is the reason

why Dallol is ranked at the bottom of the group as well.

Priority-D: Less Feasible

Danab and Arabi, which are estimated to have more than US$0.17/kWh of generation cost are

categorized as Priority-D. Their geothermal potentials are low and accessibilities to those sites are also

poor, resulting in very high generation costs.

Kone and Gedemsa are assumed to have very low reservoir temperature in the range of 130-170 °C as

mentioned above. Because only binary-type generation system, which is generally much more

expensive than flash-type generation system, can be applicable for those two prospects, they are given

the lowest priority.

As mentioned above, since Fantale overlaps the boundary of Awash National Park, the prospect is

ranked at the bottom of all prospects.

Those prospects evaluated as Priority-D are unfortunately less feasible. If social, environmental, and

technical issues are solved in some way in the future, they will become feasible projects.


5-15

April 2015


5.3 Implementation Plan

5.3.1 General Consideration

Development process of geothermal power plant before the start of generation consists of nine stages

as shown in Table 5.3.1: preliminary survey, exploration, appraisal drilling and well testing,

environmental impact assessment, well/power plant design, well drilling, power station construction

and start-up and commissioning.

In the preliminary survey like this study, data collection and surface reconnaissance are carried out and

selection of location for exploration stage for MT/TEM survey and geochemical analysis are

implemented. Based on these results, appraisal drilling and well testing, followed by simulation

analysis, are conducted in order to estimate geothermal potential. From the studies above, the scale

and depth of geothermal resources are assumed and size of power plant and its feasibility are discussed

from the point of view of economy in the feasibility study. At the same time, the environmental impact

assessment (EIA) is conducted. After approval of EIA, well drilling of production and reinjection well

and power station construction are started based on the detailed well/power plant design. Construction

of transmission line connecting to the geothermal power plant is basically the responsibility of EEP.

Table 5.3.1 Simplified Geothermal Development Period


The preliminary survey was carried out for all prospects and geophysical survey (MT/TEM survey)

was done in Tendaho-2 (Ayrobera) and Boseti prospects. In Aluto and Tendaho area, MT/TEM survey

and exploration well were already carried out while Aluto-l (Aluto-Langano) has started geothermal

power generation. Thus, taking into consideration the development status, which allows omitting the

preliminary survey and exploration, development plans for each prospect with respect to the fastest

case are discussed in the next section based on the model case above.

5.3.2 Development Plan

Table 5.3.2 shows overall schedule of geothermal power development taking into account the fastest

case discussed in previous section. In the short-term, a total 610 MW of geothermal power plants

committed by several donors is developed. In the medium-term, the geothermal prospects of

1 Preliminary SurveyData collection, Site reconnaissance, Inventory survey, Site selection

2 ExplorationGeological/Geophisical/ Geochemical survey,Sounding (MT/TEM, Seismic), Pre-feasibility study

3 Appraisal Drilling & Well TestingSlim hole, Appraisal well, Well testing, Stimulation,Reservoir simulation

4 Feasibility Study Feasibility study

5 EIA

6 Well/Power Plant Design Well design, Power plant deisgn

7 Well Drilling Production/Reinjection wells

8 Power Station Construction Power plant, Steam gathering system

9 Start-up & Comissioning

Stageyear

1 2 3 4 5 6Tasks


5-16

April 2015


Priority-A and -B are aimed to be developed. As mentioned in section 5.2.1, those geothermal power

plants above are more economical than wind and solar power. From the point of view of the least-cost

power generation, a total 1,200 MW of wind farms and solar power generation plan in EEP master

plan should be delayed, and geothermal development should be advanced instead. Therefore, adding to

1,200 MW of the target installed capacity in medium-term, an accumulated total installed capacity in

the medium-term is 2,400 MW. In the long-term, other prospects are expected to be developed.

Table 5.3.2 Overall Schedule of Geothermal Power Development


Short-term (2014–2018)

The development plan of Aluto-1 (Aluto-Langano), Tendaho-1 (Dubti), and Tendaho-3 (Allalobeda),

which were committed by several donors, and Corbetti, which was licensed by RG, are summarized as

shown in Table 5.3.3 below. From 2015 to 2018, a total output of 610 MW from the geothermal power

plants will be developed in the short-term in this master plan. Those geothermal development projects

are not reflected in the EEP master plan shown in Table 2.3.1. Therefore, it is necessary to revise the

development plan in the short- and medium-term based on those projects. The committed geothermal

power plants and large-scale hydropower plants under construction, such as the grand renaissance dam,

are expected to generate much more electricity than the forecasted electricity demand in the short-term.

Therefore, it is considered important to delay development of other electricity sources planned in EEP

master plan. However, overall development process of some geothermal projects may be delayed due

to the interruption of appraisal drilling. The Ethiopian government should monitor the development

process carefully and move ahead with the development plan to meet its reviewed schedule.

14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37

◎

◎

◎

◎

◎

◎

◎

◎

◎

Lisenced by RG ◎

Lisenced by RG ◎

◎

◎

◎

◎

◎

◎

◎

◎

◎

◎

◎

◎

◎

◎

◎: Commencement of Operation

15

16

17

-

-

-

10

9

12

11

13

14

5

-

6

7

8

S

-

1

2

3

4

Short-term Medium-term Long-term

S

S

S

2018

-

-

total

-

3701

Sub-total

2400 -

691 -

-

0.1047

2036

-

-

0.0726

0.1019

0.1643

0.1907

0.0731

0.0971

0.0974

0.1017

0.1017

Sub-total

Sub-total -

-

-

0.0572

0.0585

0.0717

0.0592

0.0609

0.0624

0.0585

0.0720

2036

2027

2027

2029

2029

2029

2030

2030

2036

2036

44

11

7

37

14 2036

-

120

9

390

33

230

100

86

2024

110

50

180

95

500

790

265

130

2021

2021

2021

2022

2024

2024

RankingOrder

Cost ofGeneration(US$/kWh)

25 2017

500

Kone

Fantale

Year of 20**

CODInstalledCapacity

(MW)Prospect

75 2018

10 2018

Boina

Dofan

Dallol

Danab

Arabi

Gedemsa

Boseti

Meteka

Teo

Tulumoya

Nazareth

Damali

Aluto-3

Tendaho-2

Tendaho-3

Corbetti

Abaya

Tendaho-3

Corbetti

Aluto-1

Tendaho-1

Tendaho-1

Aluto-2

25 610 610

280 2020

2020

610 610 610 610 610 610 610 610 610 610 610 610 610 610 610 610 610 610 610

25 610 610 1000 1325 1825 3902 39021825 3010 3010 3010 3409 3409

2400 2400

3772 3902 3902 3902

2400 2400 2400 2400 2400 2400

3902 4091 4091

390 715 1215 1215 2400

892 892

2400 2400 2400 2400

892 1081 1081

2400

399 399 762 892 892 892


5-17

April 2015


Table 5.3.3 Short-term Development Plan

Source: JICA Project Team (Development plan were referred to published documents of several donors)

Medium-term (2019–2025)

According to economic evaluation, the Priority-A and -B prospects are more economical than other

power generation schemes such as wind farms and solar power. Therefore, their development should

be prioritized over other power generation schemes in terms of least-cost power generation plan. EEP

master plan has an expected total of 1,200 MW from wind farms and solar power generation which are

not specified projects in the short-term up to 2018. The JICA Project Team would like to propose that

wind farms and solar power generation projects that are not specified should be delayed and

construction of geothermal power plants, which are mainly planned in the long-term, should be moved

forward instead.

Table 5.3.4 presents the geothermal development plan in the medium-term. Priority-A prospects are

aimed to be developed by the year 2020 or 2021. Among the Priority-A prospects, Aluto and Tendaho

area has some initial development activities such as geophysical exploration and drilling survey in the

short-term and there are planned exploration by several donors, such as deep well drilling in

Tendaho-1 (Dubti) funded by the Agence Française de Développement (AFD), MT survey in Aluto-2

(Finkilo), Aluto 3 (Bobesa), and Tendaho-3 (Allalobeda) by the World Bank (WB) and Icelandic

International Development Agency (ICEIDA). Utilizing the results of those activities to shorten the

process of Aluto and Tendaho projects, it is possible to start their operation by 2020 to 2021 at the

earliest. Boseti and Meteka prospects of Priority-B are planned to start operations in 2025 which is the

final year of the medium-term. Since there is sufficient preparation time for those prospects, GSE is

expected to carry out detailed exploration to evaluate the possible geothermal resource amount and to

plan for a drilling survey at an earlier time.

Rank SiteInstalledCapacity

(MW)COD

ICEAE/NFD/WBStart-up & Comissioning

RGStart-up & Comissioning

WB/GoJStart-up & Comissioning

AFDStart-up & Comissioning

SAluto-1 (Langano)

75 2018

500

Development by Donors

Corbetti

2014 2015 2016 2017 2018

2018

STendaho-1 (Dubti)

10 2018

STendaho-3 (AllaloBeda)

25 2017

S


5-18

April 2015


Table 5.3.4 Middle-term Development Plan



(MW)COD

GSE (ELC) 2013 Preliminary SurveyAFD Exploration (MT survey)

AFD Appraisal drilling (Two Full size well)Feasibility Study/EIA Financial dicision on the 100MW project at the beginning of 2016

Well/Power Plant DesignWell Drilling

Power Station ConstructionStart-up & Comissioning

JICA Preliminary SurveyICEADA/NDF Exploration (MT Survey)

Appraisal Drilling & Well TestingFeasibility Study/EIA

Well/Power Plant DesignWell Drilling

Power Station ConstructionStart-up & Comissioning

JICA Preliminary SurveyICEADA/NDF Exploration (MT Survey)

Appraisal Drilling & Well TestingFeasibility Study/EIAWell/Power Plant Design

Well DrillingPower Station Construction

Start-up & ComissioningJICA Preliminary Survey

JICA Exploration (MT Survey, etc.) (JICA) Appraisal Drilling & Well Testing (Slim hole/Full size well)

Feasibility Study/EIAWell/Power Plant Design


Start-up & ComissioningICEADA/NDF

ICEADA/NDF Exploration (MT survey)ICEAD/NDF/WB Appraisal Drilling & Well Testing (25MW Development)



Start-up & ComissioningDevelopment by RG

Start-up & ComissioningDevelopment by RG

Start-up & ComissioningJICA Preliminary Survey

JICA Exploration (MT Survey, etc.) Appraisal Drilling & Well Testing


Well DrillingPower Station ConstructionStart-up & Comissioning

JICA Preliminary SurveyExploration

Appraisal Drilling & Well TestingFeasibility Study/EIAWell/Power Plant Design

Well DrillingPower Station ConstructionStart-up & Comissioning

2015 2016 2017 2018 2019 2020 2021 2022 2023 2024

B Abaya 790 2024

2014

ATendaho-3 (Allalobeda)

95 2021

A Corbetti 500 2022

ATendaho-2 (Ayrobera)

180 2021

AAluto-3 (Bobesa)

50 2021

Tendaho-1 (Dubti)

280 2020

AAluto-2 (Finkilo)

110 2020

2025

B Boseti 265 2024

B Meteka 130 2024

A


5-19

April 2015


Long-term (2026–2037)

Since most of the hydropower potential in Ethiopia is expected to be developed in the long-term and

electricity demand is forecasted to exceed 20,000 MW in the early 2030s, more geothermal potential is

anticipated to be developed. In this master plan, all geothermal potential is planned to be developed by

2037 as shown in Table 5.3.5.

In this study, characteristics and temperature of geothermal reservoir is evaluated by brief surface

reconnaissance and geochemical analysis and by analysis of existing data in some prospects where the

site survey is impossible for security and access reason. In order to clarify the scale and temperature of

the geothermal reservoir in more detail to discuss their feasibility, it is necessary to carry out the

detailed exploration.

Table 5.3.5 Long-term Development Plan


5.4 Financial Considerations for Geothermal Development

This section discusses financing aspect based on several funds. Due to its lack of own funds, the

government cannot help but resort to external funds for geothermal development. The JICA Project

Team sees four possible sources of funds: Word Bank ODA loans, Japan's ODA loan, commercial

banks loans and bonds issue. Their financing conditions (interest rates and repayment periods) are

summarized in Table 5.4.1. In this calculation the capital costs are annualized using the interest rate

and the repayment period of each fund. This is in contrast with calculation of economic costs of

generation in Section 5.2.1 in which the capital costs are annualized using a discount rate of 10% and

an economic period of 30 years. Then the financial costs of generation thus calculated (hereafter called

'cost of production') are compared with the tariffs to see which funds are financially feasible. The

tariffs might include transmission and distribution costs, but due to their smallness against generation

costs and simplicity, the costs of generation are directly compared with the tariffs.

At present, the generation cost by dominant geothermal power plant in Ethiopia is estimated around

US$0.05-0.06/kWh. On the other hand, the Ethiopian power market is receiving a large amount of

subsidy to suppress the selling price of domestic electricity to about US$0.015-0.04/kWh, average

US$0.03/kWh. And electricity has been exported at about US$0.07/kWh to neighboring countries such

as Djibouti, based on the PPA between the countries. Figure 5.4.1 shows the comparison with capital


(MW)COD

C Teo 9 2027 9 9 9 9 9 9 9 9 9 9 9C Tulu Moye 390 2027 ## ## ## ## ## ## ## ## ## ## ##C Nazareth 33 2029 33 33 33 33 33 33 33 33 33C Damali 230 2029 ## ## ## ## ## ## ## ## ##C Boina 100 2029 ## ## ## ## ## ## ## ## ##C Dofan 86 2030 86 86 86 86 86 86 86 86C Dallol 44 2030 44 44 44 44 44 44 44 44

D Danab 11 2036 11 11

D Arabi 7 2036 7 7D Gedemsa 37 2036 37 37D Kone 14 2036 14 14D Fantale 120 2036 ## ##

2026 2027 2028 2029 2030 20372031 2032 2033 2034 2035 2036


5-20

April 2015


costs of each condition and existing power price (consumer price). It is assumed that the existing

subsidy would be maintained.

Even the Priority-A geothermal prospects, which is estimated to have the lowest capital cost of

US$0.0301/kWh in the case of yen-loan by the Government of Japan (GoJ), has a slightly higher

selling price of domestic electricity. On the other hand, the Priority-A and -B prospects are below the

export price of US$0.07/kWh in the case of official development assistance (ODA) by WB and GoJ.

In the case of loans by commercial banks and bonds, all prospects are over US$0.07/kWh. Thus, the

project cost for geothermal development needs to be financed by WB or GoJ loan, or equivalent

condition.

Table 5.4.1 Possible Funds Loan Conditions

Item ODA-WB ODA-GOJ Commercial Banks Bonds

Interest (%) 5.0 3.0 6.0 5.0

Repayment period (year) 20 30 10 7

Source: IDA

Source: JICA Project Team (Fund procurement condition is referred to IDA)

Figure 5.4.1 Tariff and Production Cost using Several Funds

0.0000

0.0500

0.1000

0.1500

0.2000

0.2500

0.3000

0.3500

Tendaho-1(D

ubti)

Aluto-2 (Finkilo)

Corbetti

Aluto-3 (B

obesa)

Tendaho-2

(Ayrobera)

Tendaho-3

(Allalobeda)

Aluto- 1 (L

angano)

Abaya

Boseti

Meteka

Dofan

Teo

Tulu M

oye

Fantale

Nazareth

Dam

ali

Dallol

Boina

Danab

Arabi

Tar

iff

(US

$/kW

h)

Production Costusing ODA-WB

Production Cost using Commercial

Production Cost using Bonds

Production Cost using ODA-GOJ

Domestic Tariff:2.8 cents/kWh

Export Tariff:7.0 cents/kWh

Priority -APriority -B

Priority -C

Priority -D


5-21 April 2015


5.5 Implementation Structure

5.5.1 Consideration of Structural Body for Geothermal Energy Development

(1) Energy cost and Structural Body

As stated in Chapter 5.4 above, the energy cost in Ethiopia ranges from US$ 0.07-0.08/kWh, whereas

the retail electricity price ranges from US$ 0.015-0.04/kWh (average US$ 0.03/kWh). The GoE

presently subsidizes this gap. For export, the price is set at US$ 0.07/kWh according to the PPA with

Djibouti. Thus, the energy cost of geothermal power generation shall be below the presently adopted

electricity retail tariffs under the conditions of the present energy price policy.

IFC conducted a case study where four value chain models for geothermal power generation were

assumed, and presented a tariff variation for each case. Tariffs here are defined as the sales tariffs

charged for the electricity generated by the geothermal power plant at the delivery point to off-takers

(Figure 5.5.1). For the four cases, it was assumed that the private sector will construct and conduct

operation and maintenance (O&M) of the power plant, except for the case of the fully public model.

For the US$ 0.15/kWh tariff level, a full private model (except for pre-survey) may be used,

For the US$ 0.12-13/kWh levels, the private sector may enter at the test drilling stage,

For the US$ 0.10/kWh level, private entry after the test drilling stage may be possible,

For the US$ 0.05/kWh level, all the upstream activities should be undertaken by the government,

leaving the power plant construction and operation to the private sector, and

For the US$ 0.03/kWh level, only the fully public model may be used.

With the current tariff levels, possible and sustainable options are a fully public model for the

domestic supply project, and Models C or D for the export supply project. However, it will be a

reasonable option wherein geothermal power plants will be used for domestic use rather than

hydropower, which is susceptible to seasonal fluctuations. Therefore, fully public model may be the

best option for geothermal energy development.


5-22

April 2015


Figure 5.5.1 PPP Model Options and Tariff

(2) Pros/Cons Analysis of GSE and EEP and Proposal of New Organization

The Business Models C or D and fully public model will only be sustainable under the present

national electricity price policy. Under these models, public entities shall conduct work up to at least

the test well drilling stage. Presently, GSE and EEP are the only public entities that could undertake

the mandate. The IFC (International Finance Cooperation) of a World Bank Group presented a

pros/cons analysis of these entities. The analysis also assumes a new entity. A summary of the analysis

is as follows:

1) Pros/Cons Analysis of GSE and EEP

Pros/cons analysis for surface survey and test drilling are as follows:

The existing GSE has legal mandate to undertake geotechnical investigation and exploration

activities. The GSE geothermal directorate is especially dedicated to geothermal development.

They have limited experience and/or insufficient resources in terms of manpower and equipment.

The existing EEP is presently involved in Aluto and Tendaho projects. They have no legal mandate

for geothermal development. The commercially operating EEP might be unmatched with high risk

exploration works.

A new, special purpose entity (presently non-existing) with mandate to focus on geothermal

resources may address all the shortcomings of the two existing entities and accelerate rapid

geothermal development, although it requires new laws and regulations that may take time to set

up.

Pros/cons analysis for field development:

The existing GSE has test drilling experience although manpower and financial capabilities are

limited.

The existing EEP is willing to do field development in Aluto-Langano and may be able to raise

funding easily, although they do not have sufficient manpower, equipment, and technical

Plantconstruction

Fielddevelopment

F/S &planning

Testdrilling

Exploration

PreliminarySurvey

Operation

Field Plant

Public Private

Public Private

Public Private

Public Private

Public

Public Private

(Source) IFC

Tariff($/kWh) Remarks

0.15

0.13

0.10

0.05

0.03

Corebetti

Tendaho

AlutoLangano

A

B

C

D

FullPublic

Busi

ness

Mod

el


5-23

April 2015


experience.

A new, special entity (presently non-existing) may rapidly accelerate geothermal development.

2) Restrictions of Existing Organizations and Proposal of New Special Purpose Entity

Figure 5.5.2 summarizes various options of models C, D, and fully public model. Figure 5.5.2 includes

the case where one unified entity undertakes production and sale of steam as well as power generation

because there are similar cases all over the world including GDC in neighboring Kenya. Examples

were explained in the latter part of this section as reference. On the other hand, a fully private model

such as the one that is being operated in Corbetti is not included because the overall business model is

not clearly announced at this stage.

An analysis is described below in accordance with Figure 5.5.2.

Since the existing GSE is responsible only for geoscientific research activities, GSE may not

undertake production well construction and the work thereafter. Therefore, an amendment of the

existing laws and/or regulations shall be necessary for Option D-1 and Option FPc-1. Similarly,

since the existing EEP is responsible for generation, transmission, and distribution of electricity,

they may not undertake geoscientific survey in Option D-3 and Option FPc-3 without amendment

of existing laws and/or regulations. However, even if the relevant laws and/or regulations were to

be amended, the following issues shall be addressed.

Even though it is not necessary to get a mandate from the Ministry of Water, Irrigation and Energy,

EEP is undertaking confirmation well drilling in Aluto-Langano. This corresponds to Models D-2

or FPc-2. In the Project, the actual drilling works are conducted by GSE in the field under the

project manager from EEP. Possibly due to insufficient EEP experience in geothermal development

management, the project tended to be behind schedule. Therefore, it is indispensable that EEP

capacity shall be enhanced for geothermal development if these options are to proceed.

However, such capacity enhancement will result in competing or duplicating mandate against GSE

under the Ministry of Mines. Therefore, coordination or cooperation will be indispensable between

the two public entities. That being said, however, coordination/cooperation of two entities, each

under different ministries, will usually be difficult. Thus, it is recommended that

geothermal-related sections of those two entities shall be merged into one public entity.

Such new entity shall be formed under the Ministry of Water, Irrigation and Energy because the

main purpose of geothermal development is for electricity development. There will be two options:

the first option is to merge them under EEP and the other is to establish a new entity outside EEP.

The first option may not be suitable because: (i) EEP is presently undertaking large-scale

hydropower projects so vigorously that geothermal development priority will be kept low, and (ii)

the commercially operating EEP might be unmatched with high risk exploration works, which may

render management complicated. All of these may hinder smooth development of geothermal

energy.


5-24

April 2015


From the above analysis, it is recommended to establish a new special purpose entity that

undertakes geothermal energy development-related services, under the Ministry of Water,

Irrigation and Energy.


Figure 5.5.2 PPP Models for Geothermal Development in Ethiopia

5.5.2 Special Purpose Public Entity (Enterprise)

(1) Establishment of Special Purpose Public Entity (Enterprise)

The recommended new special purpose entity is temporarily named as Ethiopian Enterprise for

Geothermal Energy Development (EEGeD). The business models of EEGeD are the Models D-4, FPc-4,

and FPc-5. EEGeD could deal with the Model C-1 and C-2, if the private sector will undertake the

operation from the start of field development. As can be seen from the figure, the mandates of EEGeD

may be as follows:

To undertake the geothermal resource surface survey and test drilling,

To undertake project feasibility study when necessary for future business of EEGeD,

To undertake field development wherever possible, and

Middle Off-taker

PreliminarySurvey

ExplorationTest

DrillingF/S,

PlanningField

DevelopmentPower PlantConstruction

Operation EEP

FPc-5

GSE EEPSteam: EEP

Power Plant: PrivateEEP

EEP

EEP

EEP

EEP

EEP

EEP

EEP

EEP

-

Power Plant: PrivateGSE GSE(*)

Steam: GSE(*)

C2Power Plant: EEP

-Steam: Private

GSE GSE(*)Power Plant: EEP

Steam: GSE(*)

D1

D2

D3

New EnterpriseSteam: New E.

D4Power Plant: Private

EEP(*) EEPSteam: EEP

Power Plant: Private

Power Plant: Private

(*) GES is not in charge of Fielddevelopment and/or Steam sales

FullyPublicModel

New EnterprisePower Plant: New

Steam: New E.

FPc-1

Notes

(*) GES is not in charge of Fielddevelopment and/or Steam sales

-

(*) EEP is not in charge of exploration

-

C1

Early Late

Development Stage

BusinessModel-D

BusinessModel-C

-Steam: Private

EEP

GSE EEP

EEP(*) EEP

EEP

Power Plant: EEPSteam: EEP

Power Plant: EEPSteam: EEP

Private

Private

GSE (or New Enterprise)

GSE (or New Enterprise)

D1, D3, FPc1, FRc2

D2, FPc3

D4, FPc-4, FPc-5

C1, C2 In Model C1 and C2, the New Enterprize may handle the work upto Test Drilling

In Model-D, FPc-4 and FPc-5, the New Enterprize will undertake steam prodution and sales.

EEP Capacity for geothermal development shall be enhanced, GSE and EEP shall be well coordinated (D2, FPc-2)

Amendment of regulations for GSE and EEP is required (D1, D3, FPc-1, FPc-3)

FPc-2 Present Aluto Langano Project

(*) EEP is not in charge of exploration.

-

FPc-3

FPc-4 New EnterprisePower Plant: EEP

Steam: New E.

GSE

GSE


5-25

April 2015


To operate steam production and sales wherever possible.

However, the current move to privatization will likely become more evident in the future with various

financial and/or regulation arrangements. Therefore, the establishment of EEGeD shall not hinder the

private sector from participating in geothermal development at any stage.

There may be a possibility that EEGeD may extend its operation to power generation. However, it may

be prudent that the mandate of EEGeD should be concentrated to geothermal-related matters since even

this mandate necessitates highly specialized knowledge and experience.

The merits of forming EEGeD are as follows:

EEGeD will be able to concentrate its efforts to geothermal development mainly for the purpose of

electricity generation;

EEGeD will also be able to accumulate its knowledge and experiences within the organization,

which will accelerate geothermal development; and

EEGeD, as the single focal point for geothermal development in Ethiopia, will be able to attract

donors’ attention, which will make financial arrangement much easier.

(2) Establishment of EEGeD

The new geothermal-specialized public entity EEGeD shall be financially sustainable once it becomes

a fully-fledged operation. It is for this reason that EEGeD shall undertake steam production and sales,

thereby ensuring stable revenue. It is understood that a public entity in Ethiopia named “Enterprise” is

defined to be financially sustainable.

Designing of a proper institutional and regulation framework and formulation of implementation plan

of the new enterprise EEGeD will be necessary. A master plan project will be proposed in Chapter 9 in

this report.


5-26

April 2015


5.6 On Direct Use of Geothermal Resources

5.6.1 Present Status of Geothermal Resource

(1) Direct Uses of Geothermal Resources in the World and in Japan

Table 5.6.1 shows the present status of direct uses of geothermal resources in the world and in Japan

Geothermal resources are widely used for bathing/pools, indoor heating, and greenhouses in the world

whereas there are only nominal uses for others. On the other hand, it is used in Japan largely for

bathing – Onsen bathing followed by snow melting.

Table 5.6.1 Present Status of Geothermal Direct Uses in the World and in Japan

Geothermal Direct Uses World (15,346 MW) Japan (2,100 MW) Bathing/swimming pool 44% 87%

Heating 35% 4% Greenhouses 10% 2% Fish farming 4% 0%

Industrial utilization 4% 0% Space cooling/snow melting 2% 7%

Agricultural drying 1% 0%

Source: Lund et al. (2010)

(2) Direct Uses of Geothermal Resources in Ethiopia

In Ethiopia, geothermal resources are used by local people mainly for hot spring or steam bathing. In

Sodole, there is are large-scale state operating recreational facilities; and hot spring bathing facilities

are available in Addis Ababa and in the southern part of Ethiopia. In Nazareth (Boku), there is a state

operating sanitarium facility, and there are local steam bathing locations in the surveyed area.

Table 5.6.2 Geothermal Direst Use

Sites Direct User

1 Gedemsa (Hippo Pool)

There are bathing facilities that draw water from nearby hot springs. Local residents use them for hot spring curing and washing as well.

2 Nazareth (Boku) There are small rooms above the fumaroles for vapor bathing and cure. There is a state operating accommodation. The whole area is prepared as recreation area or sanitarium facility.

3 Nazareth (Sodole) The whole area, including hot springs, is utilized as a recreation center and tourist attraction, where swimming pool and bathing facilities are equipped with restaurants and accommodations.

4 Boseti (Kintano) The fumaroles are covered by rock fences. They are utilized as steam baths.

5 Meteka There are bathing facilities utilizing nearby hot springs. Local residents use them for hot spring curing.

6 Bobessa (Gebiba) People gather water by covering the fumarole with tree branches for cooling the vapor into water.



5-27

April 2015


Gedemsa (Hippo Pool) Nazareth (Boku)

Nazareth (Sodole) Boseti (Kintano)

Meteka Aluto-2 (Bobessa: Gebiba)


Figure 5.6.1 Geothermal Resource Direct Use in Ethiopia


5-28

April 2015


5.6.2 Proposals for Direct Uses of Geothermal Resources in Ethiopia

(1) Lindal Diagram

The general application guidelines for direct uses of geothermal resources are systematized as Lindal

Diagram (Jon S. Gudmundsson, etc., 1985). Hot spring not hotter than the body temperature is used

for fish farming and swimming pools. Temperatures between the body temperature and 100 ℃ are

used for space heating including greenhouse and drying of agricultural products and stock fish. Vapor

above 100 ℃ can be used for various applications such as drying of industrial products like cement

and agricultural products like sugarcanes.

Source：Jon S. Gudmundsson, others (1985)

Figure 5.6.2 Lindal Diagram

(2) Proposal of Direct Use in Ethiopia

The following table shows the proposals for direct uses of geothermal resources in Ethiopia based on

the consideration of the existing geothermal site conditions and the current utilization of geothermal

resources.


5-29

April 2015


Table 5.6.3 Proposals for Direct Uses of Geothermal Resources in Ethiopia

Direct uses items

Contents Conditions Areas

Gardening Greenhouses

Greenhouse flower growing (export)

Suitable water available (effect: constant temperature, sterilization, photosynthesis)

Ziway lake (Aluto-Langano, Tulu Moye)

Fish farming Farming of prawns and fresh water fish (export)

Suitable water available

Ziway Lake (Aluto-Langano, Tulu Moye)

Agriculture Fruits growing (export) Vegetable growing （domestic）

Suitable water available Near large market

Ziway Lake (Aluto-Langano, Tulu Moye)

Nazareth

Leisure and recreation

Hot spa, pool, steam bath Easily accessible Geothermal site

Food processing Dry fruits Close to fruit production area Geothermal sites in Oromia, Southern Nation

Yogurt Close to milk production area Near large market

Nazareth Boseti

Coffee beans drying Close to coffee plantation Geothermal sites

Sugarcane drying Close to sugarcane plantation Geothermal site Tendaho


In addition, cascade utilization will be applicable if the geothermal source is sufficiently hot.


5-30

April 2015


5.7 [REFERENCE] Models of Geothermal Power Development in International Practice

5.7.1 International Practice

Figure 5.7.1 (R.1) shows models of geothermal power development in international practice. In many

cases, public financing is applied up to field development stage. After confirmation of geothermal

resources, private firms participate in the value chain. However, the following characteristics are

commonly observed in countries where private firms have participated in the chain (ESMAP 2012).

Open market has successfully been implemented in power generation businesses other than geothermal power generation. Parts of or all power generation businesses have been privatized.

Country investment risks are commonly evaluated low and sufficient returns can be ensured.

Central government of local governments promote private investment.

In general, the countries in this group are mostly middle- and high-income countries or countries with

well-understood geothermal resources and established track record in developing them.

Figure 5.7.1 (R.1) Models of Geothermal Power Development in International Practice

5.7.2 Example of Kenya

Since 2006, segregation of power generating sector has been implemented into various specialized

organizations for achieving efficient operations in Kenya. Power generation is being conducted by

1 2 3 4 5

PreliminarySurvey

SurfaceExploration

Test Drilling,F/S

FieldDevelopment

Power PlantConstruction

Middle Stage

1Kenya(KenGen at Olkaria),Costa Rica (ICE), etc

2 Indonesia (before), New Zealand, Ethiopia (Aluto Langano) etc

2'Private

ContractorMexico (OPF model)

3 Iceland (before the crisis)

4 El Salvador (LaGeo + Enel Green Power), Japan(recent)

5 Japan （before)

5' NPC Philippines BOT model;

6 US; new IPP Project in Turkey, New Zealand, Guatemala and others

7US, Nicaragua and recently Chile; Public entities perform limited exploration. IPPs sharethe risks of further exploration and construction

8New Philippines (Chevron project), Australia and Italy (Enel Green Power), NewIndonesia with Geothermal Fund Facility, Ethiopia (Corbetti), Japan (recent)

(Original Source: ESMAP 2012, modified by JICA Team)

Private Developers

O&M

Public entities

Late Stage

Public entity (PNOC EDC) Private Developer

Private Developers(power generation)

Public entities (GDC in Kenya, Purutamina in Indonesia)

Public entities(Steam production)

Private DevelopersPublic entities

ICE: Instituto Costarricense de Electricidad, Costa Rica; CFE: Federal Commission for Energy, Mexico; PNOC EDC: Philippines National Oil Co.,-Energy Development Corporation, Philippines;NPC: National Power Corporation, Philippines; GDC: Geothermal Development Company, Kenya;

Early Stage

Private Developers

6

A Fully integrated single national public entity

Multi national public entities(Early stage by one entity and subsequent stage by other/s for an example)

Public entity (CFE) CFE

National and municipal public entities

Fully integrated JV partially owned by the government

Kenya (KenGen+GDC), Indonesia (before), Philippines (before)

Private Developers

Note

5"

Public entities


5-31

April 2015


Kenya Electricity Generating Company (KenGen）that owns 72% of installed capacity (as of 2012)

and other IPPs whereas the off-taker is Kenya Power and Lighting Company (KPLC). As for

geothermal development, the Geothermal Development Company (GDC) was established in 2008 as a

governmental special purpose vehicle that undertakes exploration and steam production as well. GDC

was separated from KenGen and was given the mandate to undertake the specialized but high-risk task

of geothermal development, whereas KenGen should concentrate its effort on power generation only

so that the electric sector itself could be more efficient.

GDC has been designed so that it gains revenue through steam production and sales. Figure 5.7.2 (R.2)

shows the general operational model of GDC. Option K-1 of GDC corresponds to the Business

Models D-4 and/or FPc-4; Option K-3 corresponds to the Business Model C-1 and/or C-2. At present,

field development is being undertaken in Menengai Geothermal Field of Kenya with Options K-1 and

K-2. It is understood GDC has already entered steam supply agreement with three IPPs (Quantum

Power East Africa, Orpower Twenty Two, and Socian Energy) and scheduled to commence steam

supply by the end of 2015.

Figure 5.7.2 (R.2) Operation Option of GDC, Kenya

5.7.3 Example of Geothermal Development in the Philippines

Geothermal development in the Philippines dates back to 1967 when small-scale geothermal power

stations were constructed in Barrio Cale, Tiwi, and Albay. Full-fledged development was implemented

in Tiwi and Makban (660 MW, 1979-1984) in Luzon, which the National Power Corporation (NPC)

constructed through the then Philippine Geothermal Incorporated. Since then, geothermal power

K-1 K-3 K-4 K-5

POWERGENERATION

PRODUCTIONDRILLING AND

POWER

STEAMDEVELOPMENT

AND

FULLCONCESSION

DETAILED SURFACESTUDIESINFRASTRUCTUREDEVELOPMENT

EXPLORATION DRILLING

APPRAISAL DRILLING

FEASIBILITY STUDY

PRODUCTION DRILLING

STEAM GATHERING

POWER PLANTCONSTRUCTIONOPERATION ANDMAINTENANCE

STEAM FIELD MANAGEMENT

(Source: GDC 2014, slightly modified by the JICA Project Team)

In operation at Menengai

GDC: Geothermal Development Company; IPP: Independent Power Provider

Optional

IPP

GDC PUBLIC PRIVATE PARTNERSHIP - OPTIONS

K-2

IPP

IPP

IPP INPUT

DEVELOPMENT STAGE

GDC

GDC

IPP

GDC

IPP

IPP

VIA

BIL

ITY

AN

AL

YS

ISIM

PL

EM

EN

TA

TI

INC

OM

E

JOINT STEAMDEVELOPMENT

GDC

GDC

GDC


5-32

April 2015


stations were constructed mainly by the Philippine National Oil Company–Energy Development

Corporation (PNOC-EDC), i.e., Palinpinon I (112.5 MW, 1983), Tongonan （112.5 MW, 1983),

Bacon-Manito (150 MW, 1994), and Palinpinon II (80 MW, 1992). In principle, PNOC–EDC

undertook the development from initial surface survey to steam production and sales whereas NPC

undertook power generation, except a few cases where PNOC–EDC also generated electricity.

In 2001, “The Electric Power Industry Reform Act” was enacted, whereby NPC was then privatized,

followed by the step-by-step privatization of PNOC–EDC from 2006. As a result, all the geothermal

power stations including Tiwi-Makban, were sold to private firms. However, the separate operational

model, i.e., steam production and sales business and power generation business have been maintained

in many geothermal power stations. The last power stations developed by the government-owned

PNOC–EDC was Mindanao II (54 MW, 1999) and Northern Negros (49.4 MW, 2007). At the former

power station, the privatized EDC continues to supply steam to a build-operate-transfer (BOT) power

generation company, and the latter has been closed down due to insufficient geothermal resource.

After privatization, there have been no particular geothermal development activities for a long time

until 2014, when the Maibarara Geothermal Power Station (20 MW) in Luzon was put into operation.

A power station (40 MW) in Mindoro is also reported to be operational in 20153.

In conclusion, PNOC-EDC, before privatization, had largely contributed to the geothermal

development in the Philippines.

Hereunder, the operation mode of PNOC–EDC and NPC before privatization is introduced, since

business circumstances in Ethiopia may be similar to that of the Philippines when geothermal power

stations were constructed4.

3 Newspaper of IEE JPAN, 5th December, 2014

4 Danilo C. Catigtig (2008), Geothermal Energy Development in the Philippines with the energy development corporation embarking into

power generation, UNU-GTP 30th Anniversary Workshop


5-33

April 2015


Source: Danilo C. Catigtig 2008

Figure 5.7.3 (R.3) Operation Mode of PNOC EDC in the Philippines

The operation mode in the Philippines is explained by Danilo C. Catigtig (2008) as follows:

The company’s steam field and power plant operations are based on a framework that covers four

types of contracts, from which its financial position is practically hinged:

Geothermal Service Contracts (GSC) with the Department of Energy (DOE) - give EDC the right

to explore, develop, and utilize geothermal resources in a certain contract area and in turn remits

to the government taxes and royalties from the net proceeds;

Steam Sales Agreements (SSA) with NPC - EDC delivers and sells steam to NPC power plants

for conversion to electricity with a minimum take or pay provision;

Power Purchase Agreements (PPA) with NPC - EDC sells to NPC electricity with a minimum

energy off-take level provision;

Energy Conversion Agreements (ECA) with BOT contractors - EDC delivers steam to the BOT

power plant and pays the contractor for the conversion of steam to electricity at a nominated

capacity; and

Energy Sales Agreement with cooperatives and DU’s - EDC sells electricity from its own

merchant plant.

5.7.4 Example - Indonesia

Geothermal development in Indonesia has been developed in accordance with Presidential Decree 45

(PD-45, 1991) in principle, followed by various amendments of laws/regulations. Geothermal power

generation is being conducted in ten sites out of 58 geothermal areas designated by the Ministry of

Energy and Mines, as of 2014. All major sites, except for a remote island, were initiated under the Nippon Koei Co., Ltd.JMC Geothermal Engineering Co., Ltd Sumiko Resources Exploration & Development Co., Ltd.

5-34 April 2015


framework enacted by the decree. PD-45 (1991) is illustrated in the figure below:

1. PERTAMINA and its joint operations contractors to develop and operate the steam field only, selling the steam to PLN or other parties for electricity.

2. PERTAMINA or its contractors to generate electricity as well as develop and operate the steam field, with the electricity produced sold to either PLN or other consumers.


Figure 5.7.4 (R.4) Geothermal Development Model before Privatization in Indonesia

The principal characteristic of the operations model is that steam development is undertaken by

PERTAMINA or a contractor who entered into a Joint Operation Contract (JOC) with PERTAMINA.

Although PERTAMINA was privatized in 2003, the presently operating geothermal power stations in

Indonesia were initiated by the then nationally-owned PERTAMINA through resource confirmation.

This is obvious in Table 5.7.1 (R.1), which shows that steam production of all the power plants that are

presently operational or to be operational are PERTAMINA-related companies except for two small

power stations in the remote island of Flores. In other words, no private firms other than

PERTAMINA-related firms have participated in test wells and steam development.

In 2011, the Government of Indonesia set up the Geothermal Fund Facility to attract private

investment for test well drilling activities. By 2013, geothermal survey license for 32 prospects was

given to developers. However, no report has reached the JICA Project Team if any test well has been

drilled in any of the 32 geothermal prospects.

From the above, it is obvious that the nationally-owned PERTAMINA played a very important role in

the development of geothermal energy in Indonesia.

ＧｏＩ Pertmina

Contractor

PLN

ESC

JOC

Exploration,Field development and Steam production, or plus power

Steam supply, or plus power supply

Steam supply, or plus

Power supply, or plus Power generation

Pertmina

PLN

ESC

Exploration,Field development andSteam production; or plus power

Steam supply, or plus power supply

Power supply, or plusPower generation


5-35

April 2015


Table 5.7.1 (R.1) Geothermal Power Stations Operational in Indonesia (as of 2015)

No. Name Province Capacity (MW)

DOC Steam Production

Power Generation

JOC/ESC

1 Kw. Kamojang, West Java 30 1983

PT. PGE PLN JOC, ESC 55x2 1988 60 2008 PT. PGE (PPA)

2 Kw. Darajat West Java 55 1994 PT. Chevron PLN JOC, ESC 90 2000 PT. Chevron JOC, ESC 110 2007 PT. Chevron (PPA)

3 G. Wayang

Windu West Java

110 2000 PT. Star Energy JOC, ESC 117 2009 PT. Star Energy (PPA)

4 G. Salak West Java 60x3 1994

PT. Chevron JOC, ESC 65 1997

5 G. Dieng Central Java 60 1999 PT. Geodipa JOC, ESC

6 G. Sibayak North Sumatra 2 1996 PT. PGE ESC 5 2007

PT. PGE (PPA) 6 2007

7 Sarulla North Sumatra (330MW) (2016) Consortium JOC, ESC

8 Kw. Ulubelu Lampung 55x2 2012 PT.PGE PLN ESC 55 (2016)

PT.PGE PLN (PPA) 55 (2017)

9 Kw. Lahendon North Sulawesi 20 2001 PT. PGE PLN ESC 20 2007

PT. PGE PLN (PPA) 20 2009

10 Kw. Ulumbu West Flores 5 2014 PT. PLN - 11 Kw. Mataloko Central Flores 1.8 2011 PT. PLN -

Source: Based on Asnawir Nasutionm and Endro Supriyanto (2011), edited by the JICA Project Team with information of “Geothermal Power Generation in the World 2010-2014 Update Report” (Ruggero Bertani 2015) and others. Shaded: after privatization of PERTAMINA; DOC: Date of Commencement


5-36

April 2015

The project for Formulating Master Plan

on Development of Geothermal Energy in Ethiopia Final Report

CHAPTER 6 GEOPHYSICAL SURVEY

6.1 Objectives

The Project Team conducted geophysical survey at two selected sites in order to provide information

for selecting test well targets.

6.2 Selection of the Target Sites

Two sites for the geophysical survey were selected from the 22 targets sites based on the following

criteria. Through the Master Plan formulation in the Chapter 5, Tendaho-2 (Ayrobera), Boseti and

Meteka were selected as high priority sites to be developed other than those sites that have been

already committed by other donors or a private firm. Among those, we selected Tendaho-2 (Ayrobera)

and Boseti for the geophysical survey. We expect GSE to conduct the survey in Meteka using

equipment newly provided by JICA for the survey.

6.3 Selection of the Target Sites

The geophysical survey conducted consisted of MT (Magnetotelluric) survey and TEM (Transient

Electromagnetics) survey.

・Survey Method

MT method with far remote reference site

TEM method with central loop system（for static correction of MT data）

・Survey Site

Tendaho-2 (Ayrobera) site and Boseti site

・The number of stations

Tendaho-2 (Ayrobera) site: 24 stations, Remote reference station at Mille

Boseti site: 30 stations, Remote reference station at Koka

・Acquired data

MT method: 3 components of magnetic field 3 (Hx, Hy, Hz) and 2 components of electric

field (Ex, Ey) in time series data (Measurement time: More than 14 hours per one station)

TEM method: 1 component of magnetic field (Hz) of transient response

・The number of frequency for data processing and analysis

MT method: 80 frequencies in the range of 320Hz ~ 0.00034Hz

TEM method: 3 kinds of repeat rate 237.5Hz, 62.5Hz and 25.0Hz


6-1

April 2015



6.4 Survey Results

The location map and the station map of the MT/TEM survey for each survey area are shown in Figure

6.4.1, Figure 6.4.2, and Figure 6.4.3. The list of coordinates of the stations is shown in Appendix-6.

6.4.1 Tendaho-2 (Ayrobera) Geothermal Field

(1) MT Survey

After the acquired data were processed using the remote reference technique, the apparent resistivity

and phase curves were created, and the data quality of each measuring station evaluated. At almost all

stations, the data quality from high frequencies to low frequencies was good. Though at some stations

the apparent resistivity curve shows a little scattering in local reference data processing, noises were

reduced and data quality was improved after remote reference data processing.

After 2D inversion analysis was carried out at eight profiles, as shown in Figure 6.4.2, which consist

of two profiles where the MT survey was conducted in the Project and the six existing profiles from

past MT surveys, the resistivity structure was obtained and the resistivity cross sections were created.

According to the results, the resistivity plan maps and the corresponding panel diagram were created.

Figure 6.4.4 shows the panel diagram of the resistivity plan maps. The resistivity cross sections, the

resistivity plan maps, and the fit of the observed data and model responses are attached in Appendix-6.

The main resistivity features of Tendaho-2 (Ayrobera) as revealed from the MT survey are as follows:

About the surveyed site, the resistivity structure is generally composed of three zones, namely,

conductive overburden, resistive zone, and conductive zone, from the surface to 5,000 m depth.

The resistivity distribution is roughly in the range of 1 ohm-m to 250 ohm-m.

At 200 m elevation, low resistivity (≤ 16 ohm-m) is widely spread all over the surveyed site.

Moreover, very low resistivity (≤ 3 ohm-m) is widely prevalent at the southwest part and

southeast part.

At 0 m elevation, low resistivity is widely spread all over the site, similar to that at 200 m

elevation and the resistivity value becomes lower. Resistivity at the southern part is relatively low.

At -700 m elevation, a low resistivity (≤ 16 ohm-m) belt is at the center of the site. Especially at

the center of the belt, the resistivity is lower at less than 6 ohm-m. High resistivity of more than

40 ohm-m can be found outside the conductive belt and high resistivity variation is exhibited

around the border of the conductive belt. The almost straight contour lines indicate resistivity

discontinuity structure.

At -1,500 m elevation, the conductive belt of NW-SE strike direction is recognized similar to that

at -700 m elevation. Comparing with -700 m elevation, the distribution pattern is similar and the Nippon Koei Co., Ltd. JMC Geothermal Engineering Co., Ltd Sumiko Resources Exploration & Development Co., Ltd.

6-2

April 2015



resistivity values are entirely higher.

At -2,500 m elevation, similar to that at -700 m and -1,500 m elevations, the conductive belt of

NW-SE strike direction is recognized at the center of the site. The difference from that at -1,500

m elevation is that the resistivity value of the conductive belt is more than 40 ohm-m.

The width of the conductive belt which is distributed from -700 m elevation to the deep zone does

not change generally and the conductive belt composes a channel structure of low resistivity to

the deep zone. That channel structure of low resistivity is rather narrow in width and shows a little

constriction around profile TDO97.

The NE-SW strike direction is clearly recognized from the shallow zone to the deep zone except

for surface ground in each resistivity plan map.

(2) Summary

The characteristics of the resistivity structure in the surveyed site are summarized in Table 6.4.1.

Table 6.4.1 Summary of MT/TEM Survey at Tendaho-2 (Ayrobera) Item Descriptions

Resistivity Structure Composed of three zones, namely, conductive overburden, resistive zone and conductive zone, from the surface to -5,000 m elevation.

Resistivity Value Ranges from 1 ohm-m to 250 ohm-m

Resistivity Discontinuity

The conductive belt of NW-SE direction is distributed from -700 m elevation to the deep zone and composes the channel structure of low resistivity at the center of the site. The resistivity discontinuity structure is indicated by the resistivity variation between the channel structure composed of the distribution of low resistivity and high resistivity. The channel structure of low resistivity is rather narrow around the profile of TDO97. This suggests resistivity discontinuity across the channel structure.



6-3

April 2015



6.4.2 Boseti Geothermal Field

(1) MT Survey

After the acquired data were processed using the remote reference technique, the apparent resistivity

and phase curves were created and the data quality of each measuring station evaluated. At almost all

stations, the data quality from high frequencies to low frequencies was good. At BST-501, the acquired

data had high scatter in low frequencies and the curve slopes are too large on its apparent resistivity

curve, indicating the existence of artificial electromagnetic noise. It seems to be the effect of the power

lines at the northern part outside the survey site. Data quality of the other stations is fairly good after

noise reduction using remote reference data processing.

After 2D inversion analysis was carried out at four profiles, as shown in Figure 6.4.3, the resistivity

structure was obtained and the resistivity cross sections were created. As described below, offset

values of static correction obtained from the results of the TEM survey were applied to the MT

observed data as input data in the 2D inversion analysis of resistivity structure. Based on the analysis

results, the resistivity plan maps and the panel diagram of the resistivity plan map were created. Figure

6.4.5 shows the panel diagram of the resistivity plan map. The resistivity cross sections, the resistivity

plan maps and the fit of the observed data and model responses are given at the end of the report.

The main resistivity features of the Boseti site revealed from the MT survey are as follows:

Generally, the resistivity structure is composed of three zones, namely, resistive overburden,

conductive zone, and resistive zone, from the surface to 3,000 m depth. The resistivity


From the surface to 50 m depth, high resistivity (≥ 63 ohm-m) is widely spread all over the survey

site. Especially at the northwest part and south part, higher resistivity (≥ 250 ohm-m) is observed.

At 1,200 m elevation, low resistivity is widely distributed at the south part and the location of its

spread coincides with the highlands at the northern slope of Mt. Berecha. The border between the

distribution of low resistivity and that of high resistivity at the northern side shows high contrast

of resistivity variation, and its contour lines are straight in the WNW-ESE direction and indicate

resistivity discontinuity.

At 500 m elevation, low resistivity is widely spread all over the site. In particular, a low resistivity

belt in the NNE-SSW direction can be found at the central part and shows less than 4 ohm-m.

From the central part to the north side, the lowest resistivity (≤ 3 ohm-m) is observed. The

distribution of low resistivity of the south part at 1,200 m elevation can be seen at this elevation

which means there is continuous distribution of low resistivity to the deeper zone.

At 0 m elevation, the conductive belt is shown similar to that at 500 m elevation, but the value of

resistivity is a little higher. The area outside the conductive belt shows high resistivity and high Nippon Koei Co., Ltd. JMC Geothermal Engineering Co., Ltd Sumiko Resources Exploration & Development Co., Ltd.

6-4

April 2015



contrast of resistivity variation is shown around the border of the conductive belt. That contrast

indicates resistivity discontinuity structure. The low resistivity distribution observed at 1,200 m

elevation cannot be observed at this elevation.

At -500 m elevation, high resistivity (≥ 25 ohm-m) is widely spread all over the site, and

compared with 0 m elevation, relatively high resistivity is observed. More than 63 ohm-m

resistivity is distributed locally. The conductive belt can be seen but its resistivity value is higher.

At -1,000 m elevation, the distribution pattern of resistivity is similar to that of -500 m elevation.

Relatively high resistivity (≥ 25 ohm-m) can be found all over the site and the conductive belt in

the NNE-SSW direction observed from 500 m elevation to -500 m elevation can be recognized

slightly.

The NNE-SSW strike direction is mainly recognized from the shallow zone to the deep zone in

each resistivity plan map.

(2) TEM Survey

The TEM survey was conducted at all stations of MT measurement. About the acquired data quality,

though data scatters were observed in a few windows of earlier time and later time at several stations,

better quality data applicable to 1D inversion analysis was acquired completely. 1D inversion analysis

of resistivity layer was executed using the observed data at each station. Layered resistivity structures,

which show resistivity variation of high-low-high from the surface to the deep zone, were obtained at

almost all stations. From the results of such, MT responses were calculated and the apparent resistivity

and phase curves were created and the offset values for static correction were estimated. After

applying the offset values to the apparent resistivity curves observed by MT method, 2D inversion

analysis of resistivity structure was executed. The list of offset values for static correction and the

results of 1D inversion analysis of resistivity layer are at the end of the report.

(3) Summary

The summarized characteristics of the resistivity structure in the survey site are shown in Table 6.4.1.

Table 6.4.1 Summary of MT/TEM Survey at Boseti

Item Descriptions

Resistivity Structure Composed of three zones, namely, conductive overburden, resistive zone, and conductive zone, from the surface to -3,000 m elevation.

Resistivity Value Ranges from 1 ohm-m to 60 ohm-m

Resistivity Discontinuity

The conductive belt of NNE-SSW direction continues from 500 m elevation to the deep zone and composes the channel structure of low resistivity at the center of the site. The resistivity discontinuity structure is observed from the resistivity variation between the channel structure composed of the distribution of low resistivity and high resistivity. The low resistivity zone found under the highlands at the northern slope of Mt. Berecha continues from the shallow zone to the deep zone. The resistivity discontinuity is observed at 1,200 m elevation, where the high WNW-ESE contrast is shown between low and high resistivity at the northern part of the survey site.


6-5

April 2015




6.4.3 Notes for Reservoir Modelling

Generally, the geological structure is deduced from the resistivity distribution obtained by data

analysis in the electromagnetic survey. By knowing the underground resistivity distribution, geology

and geological structure, physicality, existence of groundwater, hot spring, and argillation zone,

alteration zone can be inferred.

Considering the geothermal reservoirs in volcanic areas, an impermeable zone over the geothermal

reservoir is formed by the low resistivity zone regarded as clay minerals and a relatively resistive zone

under the impermeable zone is expected as geothermal reservoir. In the resistive zone, there exists a

variation of resistivity and generally, a fracture zone has high permeability so that existence of fluid in

the fracture zone causes relatively low resistivity. Considering the above, what the resistivity structure

of each survey site indicates were inferred.

(1) Tendaho-2 (Ayrobera) Geothermal Field

Considering the characteristics of the resistivity structure obtained from the results of this MT survey

and the existing geological information, and the results of the past MT survey, the shallow zone of low

resistivity is inferred to be of sediments including saline fluid or hydrothermal alteration zone and the

medium zone of high resistivity is inferred to be mainly of basaltic lava rocks. Low resistivity in the

deep zone may suggest the existence of fluids related to geothermal resource. Based on the

characteristics of the resistivity structure in the survey site, there are channel structures of low

resistivity in the NW-SE strike direction and the resistivity discontinuity across the channel structure

which shows narrow width around the TDO97 profile. These resistivity discontinuities may be

inferred having the possibility to dominate the geothermal reservoir model.

(2) Boseti Geothermal Field

Considering the characteristics of the resistivity structure obtained from the results of this MT survey

and the existing geological information, the shallow zone of high resistivity is inferred to be of

volcanic lava rocks and the medium zone of low resistivity is inferred to be of hydrothermal alteration

zone or aquifer including saline fluid. The deep zone of high resistivity is inferred to be of tuffs. Based

on the characteristics of the resistivity structure in the survey site, there are channel structures of

NNE-SSW strike direction which show low resistivity and are seen from 500 m elevation, and the

distribution of low resistivity which is seen from the shallow zone and continues to the deep zone.

These resistivity structures may be inferred having the possibility to dominate the geothermal reservoir

model.


6-6

April 2015




Figure 6.4.1 Location map of MT survey

Legend □: Survey site for MT method ◎: Reference station □: Geothermal site

Reference station for Ayrobera site

Reference station for Boseti site

点


6-7

April 2015



Legend TDH-101 ● : MT station

Existing stations and acquisition year ●: 2011 ●: 2012 ●: 2013


Figure 6.4.2 The location map of MT stations (Ayrobera)


6-8

April 2015



Legend BST-501 ● : MT station

Mt. Berecha


Figure 6.4.3 The location map of MT stations (Boseti)


6-9

April 2015




Figure 6.4.4 The panel diagram of resistivity plan maps (Ayrobera)


6-10

April 2015




Figure 6.4.5 Panel Diagram of Resistivity Maps (Boseti)


6-11

April 2015



6.5 Interpretation of Resistivity Structure in Geothermal Sites

Underground resistivity structure of a geothermal field is usually divided into three (3) zones (or

layers), Characteristics of the three zones in relation with hydrothermal alteration and temperature are

shown in Figure 6.5.1 and Table 6.5.1.

Table 6.5.1 General Interpretation of Resistivity Structurein relation with Alteration Mineral Occurrence and Temperature

Name of Zone Range of ValueInterpretation of Reservoir

Temperature Alteration/Geology

1) Resistive overburden

Up to several hundred ohm-m or some thousands ohm-m

50-100 oC<Non-Alteration Zone>Volcanic ash, alluvium, fresh volcanic rocks,etc.


Lower than 5 to 10ohm-m

100-250 oC

<Argillized (clay) zone (as cap rock)>Clay minerals such as smectite and interstratified clay minerals containing smectite layers associated with zeolites

3) Resistive zone

Up to several tens ohm-m to some hundreds ohm-m

250-300 oC<Chlorite –Epidote Zone (as a reservoir)>High-temperature condition such as chlorite, illite, epidote (and garnet), etc.

Source: JICA Project Team, referred by METI et al. (2010)

a. Alteration mineralogy and temperature b. Relationship between alteration zone and resistivity

Source: Gylfi et al. (2012)

Figure 6.5.1 General Interpretation of Resistivity Structure in relation with Alteration Minerals

Occurrence and Temperature

6.5.1 Tendaho-2 (Ayrobera) Site

Figure 6.5.2 shows the resistivity distribution maps at different elevations, EL+200 m, EL+0 m,

EL-700 m, EL-1,500 m, and EL-2,500 m.

In this diagram, low resistivity zones (less than 10 ohm-m) are remarkably dominant at EL 200 m and

EL 0 m level; a low resistivity zone extending NW-SE direction becomes apparent at El.-700 m level

and downward though the distinctiveness tends to fade out downward. The zone of NW-SE direction

that is well in accordance to the general trend of the Tendaho Graben, is considered to be an intensely

Thermal alteration starts

Thermal alteration prominent

Smectite Zeolites Dominant

Chlorite Epidote Dominant

Smectite Zeolites disappear

S-Ch Mixed layered clay

Chlorite

50 ºC

100 ºC

200 ºC

230 ºC

250 ºC


6-12 April 2015



fractured zone, delineated higher resistive zones (intact rock zones) on both side of the west and the

east. The fractured zone could be a reservoir because high permeability would be expected.

For interpreting the cross sectional model, existing information are available here in Tendaho. In

Tendaho-1 (Dubti), about 13 km south-east from the site, six (6) test wells were drilled from 1994 to

1998. Among those, TD-1 and TD-2 are useful to refer. The relevant information of the two wells was

summarized in Table 6.5.2. According to the table, the depth of the measured resistivity 5 ohm-m

ranges from 530 m to 580 m; whereas the depth of the measured temperature 245 – 250 oC ranges

from 450 m to 600 m. From this well corresponding relation between the depths of the resistivity and

the temperature, the depth of 5 ohm-m may be considered as the bottom of the cap layer or the top of

the reservoir in Tendaho area.

Table 6.5.2 Existing Test Well Data in Tendaho-1 (Dubti)

Name of Zone

TD-1 TD-2

Resistivity, (Measured

depth)

Temperature, (Measured

depth)

Alteration, Inferred Temp.,

(Measured depth)

Resistivity, (Measured

depth)

Temperature, (Measured

depth)

Alteration, Inferred Temp.,

(Measured depth) 1) Resistive

over burden

Resistive <150 ºC Non-alteration

50-100 ºC , (95 m)

Resistive <150 ºC Non-alteration ,5

0-100 ºC, (50 m)

2) Low resistive zone

<5 ohm-m, (580 m)

150 - 250 ºC, (600 m)


(350 m) <5 ohm-m

(530 m) 150 º- 245 ºC

(450 m)


(280 m)


>5 ohm-m 250 ºC Chlorite-Epidote,

250-300 ºC >5 ohm-m 245 ºC

Chlorite-Epidote, 250-300 ºC

Source: Aquator (1994) and Aquator (1995), Compiled by JICA Project Team

Figure 6.5.3 shows E-W cross section of the resistivity. In the Figure 6.5.3, it is apparent that a zone of

low resistivity goes down at the middle part of the analysis section. This low resistivity zone was

interpreted as a fault fracture zones that runs NW-SE direction, and the fault zone may be the reservoir.

From the Figure 6.5.3, it is apparent that the reservoir is capped by a low resistivity layer, and

delineated by high resistivity zones on both sides. As the layer with resistivity lower that 5 ohm-m was

interpreted as cap layer (“cap rock”), the bottom depth of the cap layer is estimated to range from 300

m to 1,200 m on the top of the inferred reservoir. Table 6.5.3 summarized the interpretation of the

reservoir structure.

It is noted that the fumaroles observed on the surface are not located on the top of the inferred

reservoir. This may be interpreted such a way that the top of the reservoir part has been completely

sealed by alteration clay and the fumaroles found the pass at a rim part where a set of manor faults

outcrops on the surface.


6-13

April 2015



Table 6.5.3 Interpretation of MT/TEM Survey Results with Alteration Mineral Occurrence and Temperature in Tendaho-2 (Ayrobera)


Resistivity Depth (GL-m) Interpretation of Temperature 1) Resistive

overburden >10 ohm-m Less than 100 m 50-100 oC


Less than 5 ohm-m Approximately

100–500 m 100-250 oC


>5 ohm-m (40–60 ohm-m)

Deeper than 300– 1,200 m

250-300 oC



6-14

April 2015




Figure 6.5.2 Schematic Panel Diagram of Resistivity Distribution and Interpretation in Tendaho-2 (Ayrobera)

Basaltic Volcanic rocks and Alluvial Sediments with salt accumulation on ground

Argillized Zone (less than 5ohm-m, more than 100 oC)

Argillized

Chl-Ep

ArgillizedChl-Ep

Chl-Ep

Chl-Ep

Transition Zone between Argillized to Chrolite-Epidote Zone (boundary: 5ohm-m, Approx 250 oC)


Fa-2Fa-1(Surface Elevation 375m)

(GL-175m)

(GL-375m)

(GL-1075m)

(GL-1875m)

(GL-2875m)



6-15 April 2015




Figure 6.5.3 Schematic Section of Tendaho-2 (Ayrobera)

6.5.2 Boseti Geothermal Site

Figure 6.5.4 shows the resistivity distribution maps at different elevations, EL+1,250 m, EL+1,200 m,

EL+50m, EL+0 m, EL-500 m and EL-1,000 m.

In this diagram, resistivity higher than 100 ohm-m observed at surface level is interpreted as a new

lava layer. The lower resistivity zones less than 5 ohm-m are remarkably dominant at EL 500 m level:

a low resistivity zone extending N-S direction becomes apparent at EL 0 m level and downward

though the distinctiveness tends to fade out downwards. The zone is well in accordance to the faults

extending to NNE-SSW direction. The low resistivity zone therefore may be interpreted as a fault zone

delineated on the both sides by resistive zones.

Figure 6.5.5 shows the WNW-ESE cross section of the resistivity. In Figure 6.5.5, it is apparent that a

wide zone (channel) of lower resistivity goes down. The low resistivity zone was interpreted in this

figure as a fault zone running NNE-SSW direction. It is apparent that the reservoir is capped by a low

resistivity layer, and delineated by higher resistivity zones on both side. Therefore, the low resistivity

zone could be interpreted as a geothermal reservoir. It was interpreted in Tendaho that the layer of

resistivity lower that 5 ohm-m would be a cap layer (cap rock), the bottom depth of the cap layer is

estimated to range fromGL- 800 m to GL-900 m as shown in Figure 6.5.5. Table 6.5.4 summarized the

interpretation of the inferred reservoir.

Herein Boseti also, the fumaroles observed on the surface are located on a rim part of the inferred

reservoir, where a fault was identified.

250 oC

FumaroleArea

Fa-2Fa-1

Argillized

Chl-Ep

SW NE


6-16 April 2015



Table 6.5.4 Interpretation of MT/TEM Survey Results with Alteration Mineral Occurrence and Temperature in Boseti


Resistivity Depth (GL-m) Interpretation of

Temperature 1) Resistive

overburden 10–150 ohm-m Less than 300–500 m 50-100 oC


Less than 5 ohm-m Approximately

500–900 m 100-250 oC


>5 ohm-m (25–40 ohm-m)

Deeper than 800– 900 m 250-300 oC



6-17

April 2015




Figure 6.5.4 Schematic Panel Diagram of Resistivity Distribution and Interpretation in Boseti

(Surface Elevation 1300m)

(GL-100m)

(GL-800m)

(GL-1300m)

(GL-1800m)

(GL-2300m)

Lava and Volcanic Depositswith hydrothermal alteration

Top of Argillized Zone (under 5 ohm-m, approx. 100 oC)

Middle of ArgillizedZone

Transition Zone between Argillized to Chrolite-Epidote Zone (boundary: 5 ohm-m, Approx 250 oC)



Chl-Ep Chl-Ep

Chl-Ep

Argillized

Chl-Ep Chl-Ep

Fb-2Fb-1

Argillized

Argillized


6-18 April 2015




Figure 6.5.5 Schematic Section of Boseti Geothermal Site

Argillized

Chl-Ep

100 oC

250 oC

WNW ESE

Fb-2Fb-1


6-19 April 2015

Documents

THE PROJECT FOR FORMULATING MASTER PLAN ON ...The Project for Formulating Master Plan on Development of Geothermal Energy in Ethiopia Executive Summary Final Report Table 1.1 Target